Tango does work and I can post some tips for you:
1. If you don't use GPS often, turn it off, all of them. If you do use GPS often, I recommend only checking Standalone and Google.
2. Backlight. Either set to automatic or a low percentage such as 30-40%
3. Sync. I do not use HTC Peep or Friendstream. So I make sure that neither are auto-syncing. This will help your battery tremendously. Only have things you rely on to auto-sync i.e. gmail, calendar etc.
4. No live wallpapers. Under no circumstances.
5. Use the least amount of widgets as possible. Whatever widgets you have on your screen, they are running in the background.
6. Refrain from using task killers.
7. If you have wi-fi, I suggest you use it whenever possible.
8. Increase sync periods. Instead of having apps sync every 3 hours, increase it to 6, or something more helpful. Again, huge battery saver.
This isn't my first HTC rodeo. My first night of having this phone, I left it off the charger for almost 12 hours with light to moderate use. On a full battery it dropped to 85%. And you have people here claiming that they drop 50%. A little tweaking can get you far.
Hope this helps =)