It all comes down to how much money you have, how much you want to play a game and how long you want to wait for a larger game library. There might be other reasons, but that's the general gist of it for me. I'm sure I'll be buying one once a game I really want to play comes out exclusively for it, and I'm sure this will happen at some point. I might buy it earlier to try things out if I have the cash, but it's hard to say anything for certain.

Having a PS3 doesn't matter to me because I have the PS3... it's not like I'm going to be giving it up the moment I get a PS4.