Wait for Piledriver, and enjoy your current rig. (Maybe try a moderate overclock)
I upgraded from a Phenom II X6 @3.4 to a 2600k @ 4Ghz. Both rigs used the same two GTX 560's in SLI and I saw very little difference in gaming.
Heh, alright, thanks. It's kind of annoying to spend £300+ on a GPU and have to wait to use it all