My last 360 purchased was an HDMI equipped Jasper Arcade.
I was a completely dedicated PC gamer myself up untill I bit the bullet and bought my Xbox,
Haven't really looked back and have since bought 2 more consoles for system link play with friends.
While I do still use my PC for the odd title that belongs on a PC such as RTS and some FPS's the Xbox has totally taken over as my "gaming rig".
As for storage, I'm still using a 20gb drive and have around 75 retail games and 15 or so arcade titles..
Yeah I'm pushed for space but 60gb would be ample (retail games are around 5-8gb or so)
Arcade titles barely anything over 500mb.. most around 40mb or so.
Winning factor for me was the simplicity..
Turn it on, press of a button and see what your mates are up to
another couple of presses and you're talking live with a bunch of friends
one more and you're all running about with pistols trying to repel the oncomnig nazi zombie invasion.
No patch hunting, no glitch fixing, pure and simple.