I'm in the PS3 camp but I don't tend to buy the games that are released for both platforms. Any PS3 owner will tell you that the best games on PS3 are the exclusives - MGS4, Warhawk, SSHD, Wipeout, Drakes, LittleBigPlanet, etc...
This is with the exception of just a few games that have been released for both and have been well made for both - for example Call of Duty 4 (BioShock is great too). Often the PS3 version of a game is inferior to the xbox 360 version. I'm stating the obvious by saying that this has been due to the laziness of certain developers making shoddy PS3 ports from a game originally done for the 360, ahem, EA, ahem.
Anyway, thankfully the situation is changing now that the PS3 is "coming into it's own" and PS3 owners have more games to choose from in stores and don't have to settle for shoddy ports. I'm pleased to read that some dual-platform games will have the PS3 as the "lead platform".
Anyway, normally I don't get involved in such debates - PS3 vs 360. Who cares which is best? However, just wanted to point out that the comparison is not really accurate.