Honestly, I would contend the idea that either one (ps3 or 360) has 'more' exclusive games than one another. The majority of games are seen on both, with a minority of games either releasing later for another one or not being on the other one at all.
You might want to figure out which one has a more comfortable controller to you, because that could be a big factor over time. Also, the 360 sometimes has battery-chargable controller backs, or rechargable; Ps3 always has rechargable. But hey, you can talk extensively about add-ons, attaching keyboards to consoles, etc, but if its not a big deal for kinect or move, it's all about your primary needs.
Do you want a certain HDD size? Do you want to be able to upgrade the HDD? Are you going to stream data between it and your computer? Are you worried about having to replace it in 1-3 years?
Either one can work with any sort of tv, pretty much. If it doesnt, the tv is probably pretty old and could just use a cheap adapter. I've heard that ps3 games will look slightly better in some games than 360, but i haven't tested that myself. Only other big issue is if you want to avoid swapping out discs in mid-game (ala FF13?)
I do think it's a good idea to get one of them at some point. There are some games which i prefer on the pc or console, just based on controller preference, and it's good to have some alternative options.
As far as price goes, try to avoid thinking about it in terms of money. It's only about a hundred or so dollar difference, and one might suit your needs better than another. Pros/cons!