A CD could hold 0.7 GB, and we look at DVDs, they can store 4.7 GB.

This is up 6.7 times!

DVDs could hold 4.7 GB, but HD DVD can hold 15 GB.

This is up 3.2 times!

HD DVD can hold 15 GB, but bluray can hold 25 GB.

This is up only 1.7 times.

As we can see, bluray doesn't have enough more storage compared to HD DVD to make HD DVD obsolete. Optical discs need to have more than a 70% increase, according to history, to be useful. In the past, we've had over 200% increases, at least. Therefore, storage isn't an issue.

And, as for PCD, I think they will be the next step, unless, maybe, its PH DVD, because it's virtually complete as it is, and would cost very little. Most people don't realize how easy it is to make proteins, though, and how very cheap it can be, as well, so PCD should see drastic price drops very quickly and be able to store huge amounts of data, very soon, at a reasonable price (not soon enough for another format not to brdge the gap, though).

Anyway, looking at the here and now, bluray doesn't justify its price with extra space, because its just not enough of a jump over HD DVD. Bluray might be the more advanced option, but its not advanced enough to win on that alone, which is why bluray had to have exclusive studios and push it with the PS3. If studio support is about even, HD DVD will win, because bluray isn't advanced enough to come out on top.

Sometimes it seem to me that my posts are to long for everyone and noone reads them.
Or my English is too bad to be comprehensive
@Rooftrellen
I spent some time in my first post about technological reserves on BR format.
It means that TDK anounced about 100Gb and 250Gb BR disk and Verbatim promised 500Gb BR disk in the nearest future
Technical posibilities of HD DVD disks are LOCKED in 15Gb per layer.
At HD DVD camp Toshiba anounced that it made 3 layers HD DVD disk with 45 Mb And promised 60 Mb in foreseen future (4 layers disk) More layers in one disk is not possible at the length of lightwave that is
used in the HD DVD technology.
So before you are going to calculate anything you'd better to read the previous posts.
According to my сalculations
This is up only 5.5 times now.
It will be only 8.3 times next year.

Nuff said

@fjtorres below

I have no any other reason to think it is paid but the words of the author. As I mentioned before he forgot a very important commonly known fact that matters. This fact is not new or known by any customer. If he doesnt know it - the article has no value because it is written by the person who doesnt have enuogh knowdge in the area he tries to discuss.

@ Rooftrellen below

Unfortunatelly even 1000 of my words will not be able to compensate someone else's lack of knowledge.
It is the lightwave length of a laser that is a deciseve factor of the storage capacity of a laserdisk. Layers can double or eve tripple the storage value but it mainly only the further advancement of a technology.
For more information you can read a corresponding wikipedia article.

The main argument against BR is its manufacture price. Yes it is corect but only at the very beggining (up to 1 year).
The second is the question if we need a BR disks of such capacity or higher. First of all I must say that for Blu-ray Disc movies the maximum transfer rate is 48 Mbit/s (both audio and video payloads together), of which a maximum of 40 Mbit/s can be dedicated to video data. This compares favorably to the maximum of 36.55 Mbit/s in HD DVD movies for audio and video data (only 29 Mbits/s for video). That means that the quality of BR movie picture can be a 27% better then HD DVD movie. Today's DVD limited only at 15 Mbit/s.
But such quality means that you need 6MB per second - 360MB per minute - 21GB per hour. This means that HD DVD is not possible to hold a movie written is such quality.
http://en.wikipedia.org/wik...

Second, JVC and some other companies (Samsung) anounced this year that their new LCD TVsets have 120Hz frame refreshment rate. Before there were only maximum 100Hz TVSets. 120Hz frame refreshment rate let obtain very natural window-like picture.
To record a movie with that high framerate you need much higher capacity. Even more then 50 Gb of dual-layered BR. Todays fraterate of DVD movies is 30 frames per second for NTSC and only 24 for PAL.
HDTV movies has 30 or 60 frames per second. To double frames we need to double transfer rate. And storage capacity corespondently.

The Economist is nobody's stooge.
They're actually a knowledgeable and generally impartial source in the pay of nobody.
And unlike a lot of posters around here, they are definitely *not* in Sony's pay.

More layers means more storage, but until someone can prove that they can go beyond the limit they can produce right now, it means nothing.

You can talk about wavelengths of light being a limiting factor, and it is, but you have to understand, the differences in the wavelength of light used us very small. Someday, when we're using light in pm to read optical discs, sure, the difference between that and now will be huge. As far as I know, HD DVD and bluray run on just about the same wavelength of light, though.

Any differences they can do because of different wavelengths, if there is a difference in layers at all, must be proven first (it was once thought humans were causing the earth to cool with polution) and then, to make it really any better, you would have to sho HD DVD cannot do the same thing. It's all theory right now.

@MrSwede

The inferior technology doesn't have to have a shorter life. The next big thing will likely be PH-DVD, if no winner is decided here soon enough, which can store 100 GB right now, or PCD that can store 50 TB of data! Bluray or HD DVD neither can stand up to that.

And if the inferior technology winning means it will only be around for 20 years (VHS went from mid 70's to mid 90's and was inferior to betamax), ok, so be it. In that time, I'll be ready to replace something anyway. Betamax would have been out at the same time, anyway. If HD DVD wins, its not going to be replaced with something with bearly more storage than bluray, but with something that blows both out of the water. Bluray winning does not mean bluray will be around for longer.

All I can guarentee is that if neither wins soon, PH DVD will take over, assuming SVOD or HVD isn't ready, but then one of them will take over, followed by PCD. Really, if you don't want to buy a new player soon, skip this whole format war. Too many huge things are very close for this to mean a winner like it did when VHS beat betamax.

@Rooftrellen: I didn´t say Blu-Ray will make HD-DVD obsolete, I meant the next format, whatever it will be, if HD-DVD wins.

"DVDs could hold 4.7 GB, but HD DVD can hold 15 GB.
This is up 3.2 times!
HD DVD can hold 15 GB, but bluray can hold 25 GB.
This is up only 1.7 times"..you´re comparing Blu-Ray and HD-DVD as if they where two different generations of formats.

Blu-Ray holds more information than HD-DVD and therefore prolongs the time between generations of storage formats and that´s what we all want, or maybe you´d prefer +1GB per generation so you can buy a new player every two months?? How much clearer can I be?

@Rooftrellen: 20 years? If it would be 20 years I wouldn´t mind at all but next gen format won´t be around for that long, trust me. I´d say give it another 5 years and a new format is out. VHS 20 years, DVD 10 years..see where I´m going? Not that DVD is dead yet but they overlap each other. I agree with you, in 20 years I will have replaced all my electronics but 20 years?? C´mon man do you honestly believe in that?

No, I don't believe it will last 20 years. I think it will last longer than 5, and I was just talking until the next thing comes out. To me, DVD's reign is over, even though most people still buy them.

However, the point is that DVD would have replaced betamax or VHS, either one. HD DVD will not have a shorter life than bluray if it wins the war, because the next thing will be so much better than either that it would replace them, regardless.

We just don't know how long formats will last. Bluray/HD DVD could last 2 more years, or they could last 50 more years. We don't know. What we do know is that a discs that we can measure in TB can be made, and that puts even an optimistic 500 GB bluray disc (and that's very optimistic, to the point of most likely being more propaganda) to shame.

"HD DVD will not have a shorter life than bluray if it wins the war", it seems as if this is the bottom line here. I do believe HD-DVD will have a shorter life and you don´t. My reasons for believing it will be short lived comparing to Blu-Ray have been discussed a thousand times already: less capacity now and and less theoretical capacity in the future, those seem to be the facts right? Now to my conclusion: More space on a storage format means it´ll last longer and stand a bigger chance of "fighting back" the new format.

Think about it this way: Blu-Ray holds ruffly 67% more than HD-DVD right(you posted so yourself)? Now if DVD´s could hold 67% more than they do today, about 8 gigs single layer = 16 gigs dual, the video quality HD-DVD/Blu-Ray offers wouldn´t be that much better than these 8/16 gig DVD´s could produce therefore making it harder for consumers to make the switch to some new tech stuff that isn´t all that different, instead companies would have to take their time and come up with something even better.

See this is my opinion, my thoughts. I think I´m right and obviously you don´t but that´s how it is.
I´m outta here! Besides there are some fresh news about HD war somewhere else so see you there Rooftrellen!