I've moved to using soft email confirmation, meaning that it doesn't prevent the user from doing anything, it just removes a message on their dashboard or whatever reminding them to confirm their email address.
Context is everything, but 99% of the time soft confirmation or no confirmation at all is fine.
I think that the idea of a soft confirmation is a very good one, and we'll be switching over to that for Chron X.
The biggest reason we want an email address at all is for password resets. We have a decently large list of customers, some paying, others playing for free.. But if you've invested months, weeks or years into the game, and you lose your password, we want to have a way to help.
Currently, if this happens, we go into the database and manually verify your billing address, time you signed up, recent activity and the like, but it's a very manual and potentially error-prone process. Giving them a way to reset it automatically would help quite a bit.
The second thing we use it for is notifications. Since Chron X is an interactive game, some users request to have us send them a note when it's their turn. We wouldn't want to start sending out turn notifications without a confirmation, to avoid having users inconvenience others. ("Yeah! Send all my turns to billg@microsoft.com, and my second email, sjobs@corp.apple.com")..
We've been debating this internally for a while, arguing between easier signup (no conf), and better security, and lower customer service time (conf).
Context is everything, but 99% of the time soft confirmation or no confirmation at all is fine.