Originally Posted by
Dannoson
I'm not a computer expert, but I think the i3 is only decent, where the i5 is probably the best. Wow, and other MMOs tend to have a greater gain from good CPUs rather than good GPUs. Those two opinions (which may be fact) leads me to believe that you will find a higher performance gain going from setup 1 to setup 2, rather than going from setup 2 to setup 3. I would personally pick #2 for those reasons. Unless I had an overabundance of money, in which case I would go for the top end.
As this may not be what you wanted, or in the format you wanted, here's my rig: i7-2630QM @ 2GHz, 8 GB PC3 10700 memory (I think that's 1600MHz), and GTX 460M. I play WoW on mostly good settings. Just with #2, your setup will blow mine away.
Edit: If you had the money, I would recommend a SSD for faster boot and load times as well.