Here is an interesting link about the new Red, and compatibility with other parts.

http://velonews.competitor.com/2012/...ibility_209270

Since I don't want the full group, because my crank/chainrings are much lighter, and my current Red RD is tuned down to 124g also much lighter. The best option appears to be all old Red with 2012 FD. I will probably buy a 2012 Cassette eventually too just to save a few grams. With 2012 Red out now older Red parts are now getting much cheaper.