Next gen consoles for sure. Getting a fancy PC might be nice, but only for a few months before you start running into problems. Before you know it your drivers will go wacky or some software will screw with certain games and half the time you won't even be able to play the games you pay for. Besides would you rather pay $400 for a next gen console or $1,500 on a gaming PC?
The next gen console will get you at least 8 years of gaming that is just as good as the average PC. I still think games on the 360 look as good as most people running games on their PC.