Depends where I am, really. While I'm here at uni, I only have my laptop, so my gaming is either on PC or last generation's handhelds. When I'm back home, I use my PS2, Xbox and GameCube more than my PC. And, when I'm travelling, which is fairly often, usually between York and home (that's about a 4 hour round trip) I only ever game using handhelds.
So yeah, a bit of a mix. I guess since I'm currently at uni, PC wins out though.