I've been seeing, under heavy use, at minimum 8 hours of use consistently since I've been through a few cycles, including bump charging the first few cycles. Also, a few things that greatly helped me:
Read somewhere that the stock blockbuster app, even if it has never been opened, has a service that updates the movie catalog in the background. Run the app, update it, and in settings turn off movie catalog updates. After doing this my battery didn't drain nearly as fast while in my pocket. I can't verify that this actually helps, but it did for me. I disabled the 4G radio since I live in a 3G area as well.
I also run Green Power as of this morning. My phone has been running over 12 hour with 3:30 of that being actual usage and I'm at 68% remaining. I have it set to 1 minute on and 10 off for data while it is locked in my pocket.
Beyond that, GPS is disabled unless I need it. So is WiFi. Brightness is at about 30%, with a widget to bump it to full when I'm outside in sunlight. I also noticed a big jump when I disabled HTC sense Facebook updates, and used stock Facebook instead. Every time I went to contacts it would download that contacts Facebook updates, which is pointless and uses data constantly under normal usage.
Of course your mileage may vary, but this all gets me through the day under normal usage, and over a half day under heavy usage.