Battery life... hum. The main things would just be diligent care of settings - for example, don't set every app to sync every 5 minutes. If you can live without an app syncing, disable the sync.
My
Speed Improvements thread actually has some good tips that will help speed and battery life. The memory topic will help kill apps when not in use, and the DroidWall topic will help keep apps from getting net access when you don't want them to - just use with caution! I could see an app trying to sync constantly and being blocked by DroidWall causing issues... So if you do block an app,
make sure it's not set to sync automatically!