The Thing about Blu Ray unlike DVD is that it's way more expandable where as DVD's maxed out at 9GB , Blu Ray can keep expanding it storage capacity and most BR players will only need firmware updates...

so if another format comes out they'll have to have something that BR can't do...good to them with that...

"there are other formats coming out later . wonder if there will be a battle or bd wins?"

Personally I think that Blu-ray will be the last Disc Format because of the steady Rise of Digital Distribution and because there really isn't a need for another format because it's not like the picture quality is going to get much better because Blu-ray already provides crisp and clear picture quality.

Digital Distribution still has a long way to go before it gets anywhere close to replacing a Physical format like Blu-ray though.

And like Danja pointed out, Blu-ray's disc capacity is expandable because there's been experimental tests completed with a single 200GB+ Blu-ray DVD, so even if there's some new format that has a higher capacity than Blu-ray, it really wouldn't be needed and the Format would more than likely fail just like HD-DVD.

Blu-ray may have more capacity in the future, but the problem is most will have to buy a new player. Most of the players(outside of the PS3) can not be updated. The 2.0 players just arrived a few months ago and the main ones selling are the lower end players that aren't 2.0 compatible. No BD-live or updates. Even the low end Sony model needs external memory.

And Blu-ray has not been adopted faster. That's PR double speak based on a duplication company selling more machines, Singulus. Blu-ray has actually sold half the movies and players DVD did in the same period. After the first two years, DVD took off. Blu-ray is still up and down around 8% average. And year three is almost over. It has never hit a billion dollars in sales while DVD was doing over 2 billion by the end of the first two years.

As far as DD. That could be closer than we think. During GDC, Onlive claimed that the key to their product was an extremely small and fast compression technology. If it works on any content, and it should, it could make DD more viable quickly. If their gaming platform isn't a success, their technology could be licensed and they would still make millions.

You can get Bluray movies for pretty cheap. I get my movies for around $16 but I get mostly Disney movies which tends to stay above most movies price anyway. Most bluray films are around $15 and with a little hunting around 10.
Of course, it won't be $2 like those DVD in bargain bins anytime soon but bluray are at fairly reasonable price these day.

Considering BR adoption rate is way faster than that of DVD back in the day I think it's holding it's own ... and as you said PS3 has already played it's part in solidifying BR as the HD Format king , but there lots of way to get BR movies for cheap , Amazon for one has really good offers..

Edit: someone beat me to it :)

In the US, it's a different story than the UK. Over here, the average price for a BR is about £15. If you're lucky, you'll see them for £10, but that's still wildly expensive compared to their DVD counterparts, even for brand new releases.