Not everyone will have the same experience with battery life. Every user Is going to have different settings that will affect how the phone uses battery consumption. Things like screen brightness, how often widgets/apps update their info, gps, WiFi, Bluetooth, network coverage, browser usage, phone calls/messages, etc.
You can look through the Thunderbolt F&Q thread for tips on how to save battery life.
You can also post your reviews... including battery life in the Thunderbolt First Impressions thread...... Or just start a battery life thread but remember to list what options you are running so we can see what's doing what.
In your settings under..About phone..Battery..Battery usage will display in percentage what's using the battery. One of the biggest drains will always be the display... So turn down your screen brightness to a reasonable amount.
I will be updating the F&Q over the next few days with some more user friendly information.