This used to be the case, but I don't think it is anymore. Consoles are cheaper and games that are specifically designed for consoles run better
This depends ALOT on the PC itself.
My own machine will run anything, and it always runs it to perfection. But then, it was built specifically for gaming. That's the problem though, is you have to be fairly specific about choosing parts and such to get a really good one. If you're using a machine not specifically made for it, it's going to be quite a bit slower. But a full gaming rig outdoes even the new consoles by a significant amount.
Not to mention the other advantage of using a PC for gaming instead of consoles: The number of games available for it is DRAMATICALLY larger. Games of all levels, from AAA games to those by small indie studios. In addition, lots of games out there for PC (particularly indie games) are often free.... I dont mean free-2-play, I mean just plain free. Finding sales and discounts on any sort of game is also much more frequent. You cant beat a Steam sale.... 75% off of random things is extremely common for them.
I dumped the consoles (the 360/PS3 generation... I still have them I just dont use them much) myself in favor of the PC, and frankly, it was the best gaming-related decision I've ever made. The amount of different games I now have on here is downright staggering.
As for wether or not I'll buy an Xbone or PS4.... time will tell. The game selection isnt even close to good enough yet. But I'm watching them. It's very interesting though to watch their sales trends and such, and see what kinds of marketing is being used for each. It seems the PS4 is in the lead right now? Or so I hear.