I have the new MacBook Pro and yes the battery isn't great. On average you're pressed to get 3-4 hours of realistic development use. I say "realistic" because all the test I've seen have been very artificial and don't mirror a typical hacker's environment (using Chrome/Firefox with a zillion tabs open) multiple electron based apps (hear: Slack, Frontapp etc), with sublime and terminals running.
This contrasts the 7-9 hours of realistic use I'd get with a 13" MacBook Air (which I still think is Apple's best machine ever made, in spite of it's non-retina screen).
Just a heads up the changes to the keyboard are terrible (especially the arrow keys layout). Surprisingly the virtual escape key hasn't bothered me as much as I thought it would, even in vim.
The other thing you should be aware is that this is the first MacBook where I get unintentional input on the touch pad when typing. It's really annoying to be writing and have the mouse jump the cursor position to another part of the doc. This is something that I experience all the time on non-apple HW (and scoff at), and it's really sad to see Apple's once perfect touch pad drop to that level.
If you're thinking of buying the new MacBook Pro, my short answer is "don't", see what you do about hanging out until the next revision or possibly switch platforms.