"for any real performance or upgrade info"
CPUs that run on 1366 are massively superior to C2D's.
however i suggest you look elsewhere if you want to upgrade;
1366 has triple channel memory, and its not that effective (Tom's did a piece on it back then)compared to double channel, but more expensive; remember that whatever you chose, it will have to run on DDR3, not the DDR2 you have on your PC. the 1366 CPUs are also expensive, though they do offer lots of power, the newer sockets (1155/56 and 2011) are better for consumers.
possibly today the best choice would be a P67, or Z68 board with a i5 2500k CPU; this changes depending on what you want to do with your PC, but if you are just looking for an harmless upgrade.
your question is too generic, we need more info :/