I happened to be poking around in Tiger's System Profiler.app, and noticed that it has a battery cycle count listed, among other battery information in the Power section under Hardware. Knowing this might be useful for people deciding whether they can live with their current *Book -- or at least with their current battery -- until Intel-based *Books appear.
[robg adds: I'm pretty sure this is new to Tiger, so I've marked it 10.4 only; if I'm wrong, please let me know. With prior versions of OS X, you had to use ioreg to get cycle count info, as explained in this hint.]

