I have several friends and colleagues who also carry either the TP or Fuse and we all seem to be at polar opposites as to whether the battery life is acceptable or not. I happen to be one of the group who is completely satisfied, but others can't seem to make it through a complete day on a single battery charge.
The difference seems to be in how we use our phones. To a person, the people who are dissatisfied with their battery life seem to want to keep every bell & whistle running all the time with no regard to whether they actually need them or not. They're automatically polling their email accounts every 5 minutes and have RSS feeds downloading in the background and all kinds things running which they don't really need. The first thing one of them does when he gets into his car is slap the phone into a holder and start the GPS program. He'll even do that for his drive home from work and he's been driving the same route at least 5 times a week for the last 6 years. >mutter mutter<
I turn features on when I need them and off when I don't and I don't use my phone as an entertainment device. My phone is a mission-critical tool that I use accordingly and I have dedicated entertainment devices which do a much better job of keeping me entertained. I typically make/receive 15-20 calls per day, send/receive a half dozen text messages, access my contacts list several times, acknowledge several appointment reminders, and download email a couple of times per day and my phone will do that for a couple of days on one charge. I should add that I keep Bluetooth running constantly. If I need to go online to retrieve some information, I do. If I need to use the GPS to find my way, I'll do that too, but I don't do these kinds of things simply because I can.
At the end of one of my "heavy use" days, my battery meter typically shows around 40-50%. On an average use day it shows 60-70%. My phone spends every night in a charge/sync cradle so this level of reserve power is completely acceptable to me.
I'd probably feel differently if I traveled for a living, though.
Pete