Well.. The GOOD news is that there have been TWO new generations of Core iX CPUs released. They are the Core i3,5 & 7 500,700 & 800 series "Lynnfield" CPUs, and the Core i3, 5 & 7 2000 series "Sandy Bridge" CPUs. The BAD news is that they're NOT compatible with each other OR the Socket 1366/X58 platform! The Lynnfield CPUs run on the Socket 1156/P55 platform, and the Sandy Bridge CPUs run on the Socket 1155/P67,Z68 platform. The OTHER bad news is that Intel will soon be releasing the Socket 2011/X79 platform to replace your 1366/X58 rig.
The best advice I can give you is to overclock your 920 and wait to see how X79 shakes out. No matter what, you'll have to replace your mobo, CPU & RAM. The 1366 platform uses tri-channel memory, the 1156 platform uses dual channel & the X79 platform uses quad channel memory (since the CPUs are just rebadged Xeons). So if you were to ditch your X58, you could just use 2 DIMMs for 4GB on an 1155 system, or you could get another kit for your X58 system and use 4 DIMMs for a total of 8GB in a quad channel board and keep the other 2 in case of a failure. Personally I would just overclock your 920 and upgrade to a GTX 560Ti or Radeon 6950 for now. Or if your budget allows, a GTX 570 or Radeon 6970. Then you can see how the new stuff plays out and then decide if a platform upgrade is prudent.