While I love both consoles and PCs, your hardware costs for the PC are extremely flawed.
For starters, a good case, power supply, DVD drive and cooler can be re-used for 10+ years. Seasonic Power supplies have 7 year warranty, cases don't really get worse over time (you just need to dust clean them) and DVD drive is not even necessary, but very cheap. If you get a Noctua CPU cooler, they will send you new brackets for any new CPU socket for the cost of shipping forever. So every time you get a new motherboard, you can reuse your Noctua CPU cooler.
The main things you need to worry about are CPU+motherboard+memory+GPU (of those 4, the GPU is the most important).
Right now you can get 8GB DDR3 for $25-35. That's plenty for any PC game.
You compared a $700 next generation console, but I think they'll be more like $350-450. Either way, you shouldn't be comparing today's PC hardware to 2013 console. In 2013, you can just buy a $225 Core i5 Haswell on a new $150 Motherboard and 8GB DDR3. A card like HD7950 (or similar level of performance) will probably cost you $200 or less by summer 2013. Add even a $25 cooler and this system overclocked will smash PS4/Xbox 720 into the ground. The core 4 components (CPU+mobo+ram+GPU) will be about $600-610.
As I said since most of us PC gamers upgrade, we just care about these 4 core components, nothing else (and perhaps a 128GB SSD for $60 for Windows). All the other components such as case, PSU, DVD drive, mechanical drives we can reuse even if they are from 2008. Plus, we can resell our old CPU+motherboard+ram. The beauty is that ram stayed at DDR3 for the last 4 years, so we wouldn't even need to buy new DDR3 for Haswell architecture next summer. Reselling old parts, even if they net $200-300 means our new GPU + new platform will cost us $300-400 out of pocket = what a new console costs.
The next point you missed is that consoles like Xbox have Xbox Live that costs $50 a year and over 6-7 years that's easily another full CPU upgrade. I am not going to deny that if you are only now entering PC gaming, you'll have additional costs such as buying case, PSU, Windows and monitor. But if you have been gaming on a PC for a long-time, the incremental costs of upgrading are not a lot if you are smart about it. For example, a $225 Haswell i5 @ 4.7-5.0ghz will not be slower in games than a $1000 Core i7 3970X.
There are plenty of solid reasons why console gaming is better - convenience, exclusive titles, social gaming in friends with split-screen multiplayer, easy of use as not everyone knows how to build a PC, but your actual costs of PC gaming hardware are exaggerated since you picked top of the line components. You can still get better graphics than a PS4 with a solid $500-600 PC upgrade next year. And also, PCs can be easily connected to the same 50-60 inch HDTV.
Personally, I am going to get next gen consoles and still game on my PC because I just love gaming in general and wouldn't want to miss out on exclusives console games, while playing FPS, strategy and all cross-platform games on the PC.