Sandy Bridge E will be more powerful than Ivy Bridge. Basically Sandy Bridge E is the high end enthusiast/server 32nm Sandy Bridge platform. It will feature 4/6 maybe even 8 core processors that do not feature Integrated Graphics Processors like LGA1155 Sandy Bridge processors do. Ivy Bridge on the other hand is a 22nm die shrink of the current 2 and 4 core Sandy Bridge chips and will be similar in performance, although I hear the IGP on Ivy Bridge will be significantly improved.
Basically Ivy Bridge = next generation mainstream and Sandy Bridge E = (probably ungodly expensive) enthusiast platform. Keep in mind that Ivy Bridge won't launch until sometime early next year and will be compatible with current LGA1155 motherboards (with a BIOS update), while Sandy Bridge E will launch later this year towards the fall and will use a unreleased (as of today) socket and chipset.
It just seems like (not at launch obviously), that the 22nm techonology will end up having better performance in the long run. Didn't they say performance was supposed to be 20 percent better than current Sandy Bridge CPUs? That seems like a lot. So for Sandy Bridge E it would have to stay consistently better than Sandy Bridge is now, by like 40 percent? Or am I just way off on my thinking here.
I just don't want to upgrade to Sandy Bridge E, and then the 22nm technology takes off rediculously well and Ivy Bridge ends up with similar performance. Kind of like how the 2600K can compete in benchmarks with the 980X.
I would have to say that Sandy Bridge E will probably still be faster than Ivy Bridge, but depending on what exactly Intel does with Ivy Bridge it could be close. Keep in mind that going to 22nm doesn't automatically increase performance, it's architecture and core count improvements that matter, and from what I hear Ivy Bridge won't have a jump in core counts and the architecture won't be an overhaul like Nehelem -> Sandy Bridge was. The four core Sandy Bridge CPUs are able to match the i7-980X in part because they have a much improved architecture, which won't be true (entirely) with Ivy Bridge vs. Sandy Bridge E. Honestly, I would wait for Sandy Bridge E to be released, look at the benchmarks and see where it stands verses LGA1155 Sandy Bridge and BD.