Earlier quoted context omitted.
I think that could be to do with some apps not being optimised yet or something. If I browse using Safari on my 15" Retina, I get ~8 hours of browsing, if I use chrome that falls massively down to ~3.5.
Ouch. But I can hardly see why that could reduce battery life so much. The new power-saving features in Mavericks shouldn't, in theory, lower the battery life. The OS should act like it did under SL unless lots of RAM is needed (I'm at 50%). I'll let the computer go through a couple of power cycles, maybe that'll fix it.
Safari has had a huge makeover to improve the amount of energy use for things like background tabs/etc.... Or even not running when occluded by another window. Small things like that add up overall.
I think this is the way forward for improving the efficiency of our software in general. I'm glad someone is bringing power use to light alongside cpu/memory/disk/network.
As for the os level stuff, have you tested the actual time under use or just looked at the estimates?