You guys are forgetting one big thing going for consoles. It's optimization. So even if the X720/PS4 have similar or weaker specs found on the PC, it can still blow the PC away. Just try playing the most graphically X360/PS3 games on a similar spec PC. It can't be done. I expect a similar cycle where the X720/PS4 beats the PC early and gets overcome once the PC hardware is so far powerful that console optimization means little. Thus, people buying hardware today thinking it's going to get them pass next gen maybe are in for a rude awakening.
No. You're the one who is in for a rude awakening. PC hardware from last year outclasses that of the rumored specs of PS4/720 that are due a year-and-a-half from now. I can't make it any simpler. Yes, optimization is important, but PCs will produce significantly better image quality on top of the better graphics due to the graphical push brought on by new consoles. A huge part of that optimization includes sacrificing image quality, such as resolution, AA, AF, real-time global illumination, low FPS target (30), lower texture resolution, etc.
Note: I'm not arguing about similar-spec machines. Those who are avid PC gamers who like pushing their hardware most likely have much higher-spec machines already. But saying that consoles will blow away PC is a huge generalization, and is just wrong.
I hope you're not one of those people who are expecting something like Agni's Philosophy on PS4/720. Of the people who bring up the same argument as you just did, many of them are also firm believers of Agni's being capable on PS4/720. You'll get a dumbed down version of that on your console @720p, 30fps, whereas a GTX680 can do it at 1080p and better image quality (unknown, but stable framerate). If not, then you can ignore it, but this is also for those who are misinformed.
Also, PS4/720 are rumored to have Jaguar cores. That's not exactly cutting-edge in the terms that it's high-end. No. Jaguar cores are low-end CPU solutions. So for those of you worrying about CPU being an issue, I don't think you should worry. Hopefully more engines utilize compute shaders effectively within the coming years, putting less strain on your CPU. I would advise to get something better than a Radeon 7750 if you don't have so already, and are looking forward to playing next-gen games at higher settings than a console.