Indeed, I would wait for a DDR3 & 6+ core Ivy Bridge as well but if you're looking to upgrade now I wouldn't go down to DDR2.

Parallisation: CPUs are optimized to run a single thread per core therefore they have a lot of cache and are able to perform complex processes such as solving partial differential equations. Wow in essence is a single thread process, yes i know they've patched it so that it can split into multiple threads however the main reason you're seeing performance increases is because load has been taken off your cpu cache not because your cpu was running out of clock cycles. (this is a guess because there seems to be no fps difference between running wow on ultra on 1 core as opposed to deafult settings, i've got a 990x that has 12MB of cache in comparison to 8MB on the 2600k.) Wow is not truly a parallel process and you are also wasting resource on communication when using multiple cores.

Umbaalo, you are looking at benchmarks that do not represent what multiboxing is in reality, be very happy with your 980x.