itwbennett writes: "Portal 2 is breaking some new ground –- at least the Sony Playstation 3 version is. 'Portal 2 marks the first time that Valve's social gaming network (and digital distribution system), Steam, will appear on consoles,' writes blogger Peter Smith. What this means is that once you link your Playstation Network [PSN] and Steam accounts 'you'll be able to keep tabs on what your Steam friends are up to from within a game of Portal 2 on the PS3,' says Smith. And, you'll be able to play Portal 2 with friends playing on PC or Mac. 'I can think of at least one other example of cross-platform gaming (Shadowrun supported both PC and Xbox players in the same game servers),' says Smith, 'but it's still very rare.'"