The PS3 is a decent console, it will have decent games and it is reliable. No, it won't play a bunch of certain PS2 games, but the 360 won't play any PS2 games (obviously). If you want to play PS2 games, keep your PS2... it's not like it will sell for much these days anyway.

As for the cost, last time I checked if you wanted your 360 to have the hard drive, HD-DVD thing, etc. then you need to pay pretty much the same amount. And games, I think, are roughly the same too. So there's no real difference outside of the fact that PS3 doesn't have a "budget" version without all the extras. Hell, they did it in the US and it didn't sell enough to warrant a European version - everyone wanted the more expensive version. Go figure.