The i5 750 might drop a bit. The new 6 cores compete rather well with it. I get the feeling a bit more that Intel will keep the i5 750 where it is, and come out with a new one that has hyperthreading enabled. This will be a bit more then the normal 750.
Then again considering that the 750 is a better gaming CPU they might just leave it alone. The new 6 cores are better at everything else though.