There are lots of ways to compare this, and superchunks reductionist method is one. Even in the reductionist method though the gap between console and entry level gaming PC is very small this time around. PC components are cheaper and even Intel HD4000 can get you a decent but not cutting edge gaming experience (L4D2 beta runs very nicely 50 fps in 720p on an Intel HD4000 under steam linux).
Cost of games is one thing I did not figure in. I know that I spend a lot on console games, I usually get them day one through downloading them and pay about 60 per game. On steam I have picked up 94 games for under $300 through sales, HIB, and buying older games, AAA titles on release day are still cheaper than what I pay for a day one WiiU release.
Free games are great and can defray the cost of the pay to play online features of consoles, if they are games you want.
For the record although I won't buy an XBone because I don't like the parent corp, some of the games did look very good at E3. The PS4 I am waiting a while yet before I decide whether or not to get one. I do own a WiiU with all the accessories, and have a linux steambox running though I don't have their hardware. There is a rumour that the alienware X51 is min spec for the steambox which is why they are now shipping linux versions of it.