When next gen hits I plan on moving to consoles for about 2 years, and then move back to PC (I did the same this gen, where I gamed mostly on PS3 until 2009 when I build a gaming PC).
I don't know however if I should upgrade now one last time for the games that are coming out in 2013, or if I should just wait.
I have a Q6600 CPU and a GTX 560 TI and just installed 4 GB of RAM (2 GB were getting slow). This setup has served me well and as I said in some other posts, even with the old Q6600 CPU I can play the last year's powerhouses (Battlefield 3, The Witcher 2) and this year's Sleeping Dogs at 1680x1050 with most/all details maxed out and get over 40 fps.
But I don't know how this system will handle Far Cry 3 and the upcoming Bioshock Infinite. I know I won't max them out, but I don't know what kind of performance I can expect from them and what details.
Should I just keep this setup and the upcoming games will run well enough on it, or do you think I should just do one last major upgrade?