I am in the same boat as you, I am wondering If I should wait or not as well. I think that if your card is good enough for you right now, you might want to hold on to it because their will for sure be new cards coming out in the next 6-8 months.
It's personal preference, but I think I am going to hold out with my 470 GTX until the new cards come out. It runs all the games I play just fine with 60+ FPS on highest settings.
Main reason I upgraded is heat, if you have a 470 gtx or 480 gtx you should upgrade because any of the new cards are way more heat efficient. I had 2 gtx 470s in SLI and when I upgraded to 2 gtx 660ti's the heat went down tremendously.
This is just another factor that you have to think about before upgrading.
My GTX 560 is certainly sufficient for me at the moment, but if i max out games I run into heat issues. I'm running most games on medium settings (MW3, BF3, Assassins Creed).
Something I forgot to mention is that my friend is interested in buying my card so this might be a good opportunity for an upgrade, as it knocks off about 120 bucks off the new card.
I think I might can fit a 7950 into my budget.
But still, to upgrade in the next month'ish, or wait till beginning of 2013?
Wait til next year - prices will only continue to drop - especially when the next generation cards arrive.
If you're running into heat issues, you should use MSI Afterburner to set a custom fan profile. You can also limit your framerate in games (so your card isn't running at 100% usage all the time) to whatever you want if you set a profile in the OSD. I use it in every game so they appear smoother.