Quite a nice refresh. 2.5Ghz quad i5 (Sandybridge-based) on the low end 21.5", all have Thunderbolt ports. The 27" can handle 12 total Thunderbolt peripherals, as well as two additional monitors for a total of three (including built-in screen).
I think I'll be going this route for my next work machine, since I rarely move my work laptop anymore now that I have an iPad.
Wow... nice! Really want an iMac for recording now.