Upgraded last night from 2.6 to 2.8 on my TiBook 1Ghz. Battery readings are a bit erratic (jumps around a lot when calculating time left: 2.50, 3.30, 2.15 in the space of 3 mins, etc), had a menu bar whiteout in Safari, and Safari unexpectedly quits on me when I load a paticular web page - but not sure if it is related.