I believe this was one of the real big surprises on E3 myself. Not so much Portal 2 and the games, but Steamworks coming to PS3 and what that implies.
Sony really scored an interesting change here, with Valve now supporting PS3, MS losing another PC/360 for PC focused developer to full multi-platform status and the strange thought of one network service - PSN - hosting another - Steamworks.
I'm going to watch this with interest. One of my preferences for PS3/PSN vs 360/Live has been that in principle (unless Sony change it) PSN is more open to free mods, maps, etc. from the community that Live (at least so much as I understand it and based on when UT3 launched) but I've been very dissapointed to see this go nowhere.
If Valve patch up the Orange Box port, get L4D onto the PS3 and use Steamworks via PSN to deliver free additional content I'd be happy to see this aspect of PC gaming I miss from consoles getting some real support on one.
Try to be reasonable... its easier than you think...
