Ubisoft made some waves last year with its own special brand of digital rights management, forcing all its PC games to require a constant online connection and dropping players should that connection be terminated.
It would appear that the venture is a failed one, since that particular requirement is no longer a function of the DRM.
You'll need to be connected in order to validate the game, of course, but after that you'll be free to actually enjoy the game you purchased at your own convenience. So far, Assassin's Creed II and Splinter Cell: Conviction can be played offline, with hopefully more following as it gets phased out.
Thus we celebrate the day Ubisoft removes something from its games that never should have been there. Hooray!