iMac 2012 Features?

What rumours are there about the new iMac 2012? I want to buy one this month and I have no idea if it's worth waiting for Ivy Bridge processors and a new display. (and probably some more stuff)

I don't really care about the display and 3.4Ghz i7 sounds fine to me. I sure need the 2GB graphics card and at least 8GB of memory.

Now.. Shall I wait or buy one this month? What do you guys think?