Okay, I have both a PS3 and just finished a new upper-range PC build (E8400->4.2GH, HD 4870) strictly for gaming only. I enjoy both, but for the serious gaming, it's all PC and mouse/keyboard. I just can't use that goofy controller with shooters on a console. However, it makes for great arcade racing like the Motorstorm series. Also, the PS3 is great to take along for a party at a friend's house and definitely makes those trips home to visit family much more bearable, LOL.
Yes, the PC will never replace the console. But some people need to recheck their math on which is TRULY less expensive. Here's my cost rundown on the two including all PC hardware (not including the PC LCD & speakers in this cost since I use it sometimes on my LCD TV with the home theater like the PS3):
PC - $870
Games - $190 (6 of them)
Total: $1060
PS3 - $400
Games - $360 (6 of them)
Total: $815
That's only about a $245 difference, and obviously, the PC is far superior in both graphics and game playability/versatility with a steering wheel for racing games, keyboard & mouse for shooters, and flight yoke (and joystick for fighters & helicopters) and rudder pedals for FSX. The PS just doesn't have that kind of fun. But, by the same token, when I come home after a hard day of work and just want to vegg out on the couch and game without cranking up the PC and all that, or, when I want to travel and take game away from home, the PS3 is it baby.