Battery Monitor Widget reports estimated mA consumption. All other data are available (%, mV and temperature).
System Tuner report accurate CPU temperature.
I own a Galaxy Nexus and I never noticed such weirdness. Note however that % is reported by Android, so if there's an issue with % values, it's in the OS.
Just checked my battery history for the past few days, and indeed couldn't find any 23%, be it while charging or discharging. That's funny. Got 4 other devices 23% is there :D