I just tried to play Diablo 3, but could not log on due to server maintenance. Blizzard requires you to be always online to play even single player campaigns. I’ve seen a lot of people rage about this, but Blizzard actually has very good reasons to do this. And they even kept you, as a player, in mind!
First of all, what Blizzard is doing is not really DRM.
Digital Rights Management is making sure you have authorization (from the providing party) to do something off-line. The best example is music. After authorizing your computer you can play your DRM protected music.
What Blizzard requires is you logging on to one of their servers to play Diablo 3. This sounds like DRM, but you are actually using Blizzard’s servers to play. And for good reason!
Diablo 3 contains several features that allow you to interact with other players. For example, you can easily interact with your friends and you can even join their games. There’s also the Auction House, where you can trade items.
These features are nothing new to World of Warcraft players, and it’s not surprising they require a central server to make sure everything is fair.
An added benefit of this always online model is that Blizzard can closely monitor how players behave in the game, allowing them to fine-tune game balance with every update the release.
So, there are many wins for the player here. The big win for Blizzard is that they can be selective about whom they allow to enter the server: only people with a valid license key.
I know it’s frustrating that you can’t play Diablo 3 on a rainy sunday afternoon when you want to. But with a modern, social game like Diablo 3, being online is an absolute must.