Do you already have a PS2? If you don't have any console from this gen, the PS2 should be your first choice, as it gets all the multiplatform titles (which happen to be almost all the top Xbox titles) and has a much better library of exclusives - unless you're modding the Xbox.
And if you really have to ask for input like this, it just means you can't justify the purchase to yourself at the present time, so you're probably better off waiting.
