Upgrade to 7970, wait for Kepler?

These are my current specs...

Intel Core i5 2500k+
Patriot Sector 5 4GB DDR3 2000MHz
Asus P8P67 Motherboard
EVGA GTX 580
Raidmax AX-850W 80+ Gold PSU
Silverstone RV03
24" 1080p LED Monitor

Should I upgrade to a 7970, or wait fro Kepler, or just stick with the 580? I always feel like getting the best card out there (which is why I went for the 580), but am not sure if it's such a good idea...My card does get a bit warm when playing BF3 @ Ultra setting with FXAA mod at 1080p, it also gets pretty warm with heavily modded Skyrim at 1080p. It gets about to the 80s or mid 70s. What do you guys think I should do? Is it really worth upgrading right now?