Funny, I would think the same thing, especially since it charges so fast. I will rarely be away from power that long, if ever, but more battery is always better. For most, I think it's more about the principle and Apple's claims. But, many of us do get 9 hours with some minor setup and/or adjustments.
It does happen (not often) that I'm on a cross-country flight and am not able to plug in both at the airport prior to the flight, and on the flight itself. My 2013 MBA was great in this situation, as on a full charge I could use it in the boarding area as well as on the 6+ hour flight and it would have power to spare.
At this point, it's more common that I will be able to plug in either on the plane, in the boarding area, or both, so admittedly I don't require more than 7 hours in most situations.
After the OS Sierra install I've used my 13" TB for about a half hour, and it has slept for about 2 hours. It is still showing 99% charge, which is way better than before. However, the time remaining estimate has dropped to 7:57, and the power usage seems to be a bit higher now (540 mAH) despite using the same apps as before. I'll track exactly how much I get on this cycle and report back.
Looking forward to seeing if I will actually get more than 8 hours on this. If so, I'll keep it.
[doublepost=1479961084][/doublepost]One thing I forgot to mention, I've noticed the same thing as some others in the thread: web browsers are energy hogs. If I quit Safari and Chrome, mAH stays around 250-350. When I open Chrome and start using it, current goes up to 800-900. I just opened Safari to write this message, and it's at 560 mAH (from 270 before Safari was opened).
On my iMac 5k I have a habit of leaving all of those apps open. Guess I won't be doing that on this machine.