It sounds like you could wait considering you've got a PC for some gaming.
There are always great overlooked deals happening like the above poster mentioned.
Also, don't always count on backwards compatibility or a price drop.
Personally, I wasn't afraid to buy now. I found this years holiday bundle for $250 and went for it because my old 360 pretty much died.
Then again, I don't plan to be an early adopter for the next generation. That's if I decide to go on at all...