Really I would say that all three can come close to eachother, but the PC can win by virtue of modifacations and upgrades. If the Xbox360's and PS3's had some sort of modular setup where the GPU module could be replaced in a way the HDD's are on the Xbox, that would definately help.
Granted for the specs those consoles have they do a good job of cranking out some fine visuals at some good resolutions. Really it just depends on what your preference is...the XBox360 33% failure mess still has me dissapointed, considering every friend I know that has a 360 is on at least their 3rd, which beats the 1-in-3 reported by MS, still a great console, and the newer ones with the lower fab and better cooling is definately a plus. MS did a lot of things right with that console, and it shows for the most part. The PS3 seems like they decided to rush it too fast because the MS machine was able to crank out such an accomplished unit where-as Sony was trying to make an overcomplicated machine to do the same things..not saying it's a bad idea as I dig the PS3, I've played on one quite a bit and do enjoy the Playstation controller much more than any xbox controller, just been used to it since the original PS.
Though with as fast as things change and have to be replaced now-a-days I hope they will continue the stronger pc-based trend on consoles, it's worked out well, but I still think a modular GPU would be a good idea...could be encased like an old NES game, with a couple of fans on it, and a PCI-e slot on one end...two screws, voila, more video powa! Which is what consoles have and will always lack after a very short period of time. Both consoles were based on aging gpus when they were released...sure their platforms and the game designs help a to extract much more out of them in a more efficient way than their PC bretheren, eventually that's not good enough.
Long ago I decided PC's were going to by my main front...I like having control of some situations, the setup. I do miss the console stability (well with the older PS2 and Xbox stuff I used to do), and some PC ports are just worthless, so I know I miss out on some great games...but this also works vice-versa with consoles. Plus with the modularity of a PC and it's continual upgrade cycle, can help strongly in IQ and sound, but at a cost and also depending on support, coding, OS stability, and a lot more things the console guys don't have to worry as much about. It's a give-and-take, I do plan to have a PS3 and 360 eventually, I may wait for the next-gen stuff to come out though...as I'm very content as a PC gamer. To each their own, and nobody is making a wrong choice, as long as you are having a great time with your investment, it's all good!
