
Blizzard's VP of Online Technologies, Robert Bridenbecker, explains why he believes Diablo 3 will benefit from requiring a constant internet connection to play. Branden Barrett of GamerGaia seems to agree with him.

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All I want is a physical disc release of remastered D2 that doesn't require online check-ins.
I've lost complete interest. Too much FOMO with seasons as it is, now it's expansions? No thanks.
The modern PC gamer is so internet-dependant that I can't see this being a super-huge issue for most fans. With gaming stores only having one tiny PC section these days, we purchase and play a good number of games online anyway.
For the record, I don't necessarily agree entirely with Branden on this. It doesn't especially bother me that Diablo 3 will require an always on connection, as this was true of StarCraft 2 and never gave me any trouble, but I don't think it's as 100% positive as it might seem. For example, a dungeon crawler like Diablo is perfect for brief periods of play while travelling, or even taking on a plane to while away the time.
What's even more striking is that this comes hot on the heels of the "real money auction house" announcement by Blizzard - it seems as if the always online requirement probably has more to do with protecting the marketplace of Diablo 3 than in improving anything gameplay related. While this is absolutely not a bad idea (in fact, with that marketplace in the game, an always online requirement is almost necessary by default), it does make me wonder whether a little too much is being sacrificed for the sake of a feature is itself still not certain to be a positive addition.