There are pretty much an even number of exclusives on either console (around 100), both a broad spectrum of both shovelware and big name titles, of all genres. So games don't really matter. You'll find what you want on either console, whatever you may play.
It really comes down to what you are going to do with the console. Do you want to play socially? Get a 360. The huge firmware update (NXE) makes it far and away better for this application. Home will only be able to bring the PS3 up to where the 360 used to be but with a much nicer interface, should it ever actually come out. Sure, you are paying for it, but the stable, centralized and unified service is well worth the cost.
Want to play media with it? Get a PS3. Hands down the PS3 blows the 360 out of the water with expandibility. Sony's official stance is put a bigger hard drive in. They want you to load it with music and video, while enjoying easily the best Blu-Ray player on the market (solely because you can update the firmware when Sony releases it). It is more or less the same story as with the PS2. That was the first DVD player for a whole lot of people. The current level of updates on the PS3 make it a damn good media player.
So, get what console suits your needs the best. Are you going to play and interact with lots of others? Or use it as a media center?
NOTE:
Of course, if you live outside the US, you might want to rethink the 360. A lot of the media-related services that it does have (Netflix, TV and movie downloads) are not as available.