It looks like the only real considerable power savings comes from power-down. To come out of power-down I would need to bring either pin 2 or 3 LOW.
The problem is, those pins are already held LOW all the time in my circuit. (HIGH when button pressed) Perhaps for version 2.
If a typical car battery is about 45 amp hours, and I'm pulling 20mA or so, does that mean it would have to run for 1125 hours (almost 47 days) to half-discharge the battery?