Seems to be about the same. There is a cheap app called "battery save" that the user/owner can set alerts for apps that are running in the background. This is the only real way to extend battery life. Apps such as AT&T Navigator, for example, really eat the batteries up.
3G or 4G really does not seem to be a factor regarding battery life.
THE GOOD NEWS:
All of the accessories such as chargers and memory cards work with the 9810. Even the battery is the same. So, I keep a fully charged battery in my briefcase all the time, just in case.
Was looking at upgrading my Storm II but nobody has the Torch 4g here yet. Does anyone use the "Whats" app or other messaging services on theirs? Just wondering if there are any other free messaging apps I've missed out on.