I use my PC for gaming as most of the games I play are FPS or RTS. A mouse is so precise compared to a controller for my needs. You also probably already own/need a computer, whereas you don't actually need a console.
I have an xbox 360 which I got pretty much exclusively for Forza 4 (very good game), and the girlfriend likes console games because she likes more casual gaming (ie. from the couch). Having said that, I find the selection of gaming peripherals (including wheel/pedal sets) to be vastly superior.
Not having to pay $60/year to watch Netflix would be nice too... every time xbox live goes down, I can't use Netflix. Never again...