So... since 7800 pretty much set the standard in cycling for years, I was expecting 7900 to be tops. Interesting review though...
http://www.cyclingnews.com/tech.php?id=tech/2009/reviews/shimano_dura-ace_7900_group09What I can't understand is why Shimano seems to be running their company like the American automakers?
I realize Electronic DA required a TON of R&D and likely is the future of cycling but @ ~$5000 not the NEAR future.
So then, if you were shimano and SRAM just released their RED groupset and it KILLED your sales not only because it was new, but because it was BETTER than 7800, why would you come out with a 7900 that is:
A. Not lighter. (Than Red by nearly half a pound)
B. Not "better" than 7800 in most ways AND in some ways WORSE!
C. Not BACKWARDS COMPATIBLE!!!!

D. Not ceramic (Although... I don't think ceramic "really" does much, but if your comp is selling it and peeps want it)
It just seems like they have their heads in the sand.