You also have to factor in whether or not you’ll need to be using a PC for other things. You can probably get by with a less powerful PC (or your current one) for email, word processing, browsing, etc., but these days you can’t really get by without an operable computer of some kind.
The console generation just started a year or so ago, so the PS4 is probably a sound investment if you want to get multiplats and the scant few exclusives that Sony has lined up. (Which as far as I’m concerned means stuff by Naughty Dog, but that’s more of a taste thing, I’m sure.)
One of my roommates has a PS4 and we’ve set it up in the living room - it does make a great entertainment centre, but personally I wouldn’t be caught dead without access to a decent PC as well.