Let's mention some cold, hard facts here.
360 games have just plain looked better than PS3 games for quite a while. This was documented again, and again, and again -- with screenshots and plenty of proof. The PS3 had the shittiest resolution scaling for something like what, at least half a year? PS2 games on it also used to look worse than the original system. So even Sony has problems with their own architecture.
The 360 is thought of as having the best ports out of the two. People who own both buy the 360 versions. This is such a regular occurrence that it can't possibly be dismissed as the developers' faults. Given what multiple respected game makers have reported, the only logical conclusion is that Sony's architecture is both underwhelming in hardware features and overwhelming in the difficulty of making games.
Sony has stated that this production difficulty is intentional and artificially inflicted upon the game developers on purpose.
For even more information on Sony's inferior hardware decisions, check out the following:
http://www.avsforum.com/avs-vb/showthread.php?t=758390
So developing games for the PS3 is indeed a lot more challenging and is simply not very cost effective because of the length involved.
Which is likely the primary reason that the same games for it have sucked total ass in comparison, and will continue to do so.
Maybe you should do a little research next time, Mornelithe.