Apparently, Apple just hasn't figured out how to get reliable performance out of the back-end it's deployed to service folks who thought paying Apple $99 a year would give them reliability in their online experience.
Will performance like that allow Apple to make businesses a meaningful offer anytime soon? One of the hypotheses regarding MobileMe was that ActiveSync licensing would allow small businesses to avoid licensing Microsoft products directly in order to synchronize data. If Apple is botching its offerings with reliability, it'll have a hard time competing to serve customers who demand it.
UPDATE: The Wall Street Journal's Walt Mossberg says of MobileMe: "at $100 a year, Apple's MobileMe service sounds great, but doesn't work." Perhaps that will wake the long-slumbering fools in charge of Apple's online offerings. But ... perhaps not.