I have OS64 and after 33 hours off charge, probably close to or over 200 emails and 50 or so txts used, plus a couple pics taken/sent/recvd and 32 minutes of phone calls I am at 55% battery life.
I think this hype about extra battery life in OS 71 is a little overkill.
It all depends on what programs you have running.
If you use any IM program your battery life drains QUICK. When I use an IM for AIM and/or Yahoo I get about a day of battery life. Also playing MP3's and Video drains battery as the screen stays active. Now that I stopped I get close to three days with normal use.