We did already know in May 2011 (just use Google) that Ivy Bridge allows more cores (i.e. more transistors) and smaller designs (22 nm tri-gate, therefore lower TDP).
...from
http://9to5mac.com/2011/05/30/ivy-bridge-chips-pushed-to-2012-macs-will-have-to-wait/
...and
http://newsroom.intel.com/community...ng-new-3-d-structure?cid=rss-258152-c1-266892
...We know from Intels press release that tri-gate transistors enable a 37 percent jump in processing speeds with low voltage requirements. For example, tri-gate transistors require less than half the power when at the same performance compared to 2D planar transistors fabbed on the 32-nanometer process....
...from
http://9to5mac.com/2011/05/30/ivy-bridge-chips-pushed-to-2012-macs-will-have-to-wait/
...and
http://newsroom.intel.com/community...ng-new-3-d-structure?cid=rss-258152-c1-266892