Did UbiSoft and those other companies offer refundable activiations? IIRC, for some of the previous games, if you activate it too much then that's it, you'll have to buy a new game. I would never support a company with a policy like that. With BF:BC2, I don't think I'll ever be able to stop the activations as long as I'm the only one using the CD-Key. Obviously I'm not looking to pirate or share the game, but it's nice to know that I'll always be able to play the game and not worry about being locked out permanately.
Over the course of time the different publishers tried different things and sometimes even altered their strategy on a given game. Initially EA's implementation of Spore & Mass Effect 1 did NOT allow revocation of activations - so, as you say, X activations and that's it. After a little while and lots of consumer complaints, they released a revocation utility that you can run (
before you uninstall the game in question) to "refund" an activation. That didn't change the underlying "only X activations and that's it" mechanism, but it made it a bit more flexible by allowing refunds. If you had a hard drive crash and never had a chance to run that utility, too bad. Recently it got a little better by integrating the revocation into the uninstall process. Other publishers like Atari never even went that far; Riddick: Dark Athena had 3 non-refundable activations and that was it, period.
You're right about BC2 - even if they take the activation servers down in the future, you'll be able to install the game fresh again, you'll just have to leave the disc in the drive when you play (which is the way I'm going to be doing it).