If you don't know, Gabe Newell was quite anti-PS3 before.
http://www.computera...cle.php?id=155309
"The PS3 is a total disaster on so many levels, I think It's really clear that Sony lost track of what customers and what developers wanted," Newell reportedly said in an interview with Game Informer.
Portal for PS3 was ported by EA and they didn't do a good job, so it's good that Valve's changed their mind about the PS3. I got the PS3 version before as Portal wasn't available for the Mac. This time around I'll probably get the Mac version.
GameInformer has a Portal 2 Hub with lots of interesting info.
http://gameinformer.com/mag/portal2.aspx