That's not right - it should show /something/ at least.
Do you have an y task killers that could be killing the batteryleft service?
Nope, I don't use any task killers. In the settings, I chose estimated % as my main display parameter, same as I always used to. But instead of a percentage, the display reads "Need lo"; whatever error message it's giving is too long to fit into a space made for a 7-character readout.
I'm going to try an un/reinstall later today.