It's not really a good/bad situation, just a broadening of options.

I am curious why you are upgrading your PC so much. My PC is five years old at this point, and the only thing I've upgraded (once) is the video card (to a budget model at that). Granted, I have watched my graphics settings slip from ultra to high to my current medium-low (for shooters; I have no issues with strategy games), but with the lone exception of Battlefield 3

, my rig is able to run every game out there at the moment (all praise to the 'console retardation effect'

). As long as you aren't determined to run everything at max settings, a decent rig should be able to keep up with most games without too frequent upgrades.
As for XBOX versus PS3, I believe the XBOX is cheaper, and is definitely more popular with a huge market share. However, the PS3 has some great exclusive titles, like MLB The Show, Resistance 3, and CCP's pending Dust 514. Then again, XBox Live seems to be more popular with indie developers than the PS Network at the moment.
I would have to do some shopping around, but if I was serious about getting a console, I think I would lean towards the PS3 a bit at this point.