Well yeah, none of the Apple laptops will do that peak battery time without everything on low. But even when it isn't, from personal experience its still very reasonable and long lasting. Enough to watch a couple movies on.
Not particularly impressed with these new rigs. Personally I think they'd be more attractive getting rid of the dumb dual graphics and just going with a good low high end chip. The last time Apple used anything close to high end in their Pro line was at the end of the Powerbook G4s and that was a 9700 Pro when everyone else had 9800s. So still, Apple went with a lower power chip. But at least it was in the 256bit area instead of these 128s.
Apple is notorious with underclocking the GPUs and not advertising it. I'd suspect they are continuing that with these NV chips after what happened with the last gens from the big NV defect fiasco. In fact, amazing they are still using NV with all the complaints customers had about them overheating. But then Apple does swing between chipmakers a lot over the years. Wouldn't be surprised if Intel had some say in it, which is why we're seeing their craptacular graphics returning.