Thanks to the hard work of the folks who purchased Valve's Potato Sack promotion, the Portal 2 alternate reality game has finished, and the long-awaited sequel is now available on Steam. The game officially releases tomorrow for consoles and PC, but since the Steam version is compatible with SteamPlay, it's also available for the Mac from day one.
Portal was one of the best games of the past few years, and every indication is that the sequel will be just as inventive and fun. If you've been waiting for it, the wait is over. Go and enjoy!