Stock downgrades are nothing new for the boys and girls at Palm, but analyst Tavis McCourt of Morgan Keegan (which certainly sounds like an important and all-knowing firm) has painted a particularly bleak picture of the company's books today -- so grim, in fact, that it set off a 20 percent drop in the company's market cap. Apparently the big concern is Palm's cash burn rate, which has left a cash reserve of just under a quarter billion dollars through a series of delays and setbacks that have been partially offset by moderate successes like the Centro. McCourt figures that'll be down to a mere $75 million by the time Palm OS 2 launches, and that's assuming they don't run into any more slips in the schedule. He notes that Bono can always just flip 'em a few more mil out of his Joshua Tree earnings, but it'll end up diluting existing shareholders' stakes, hence the massive drop in value today. No pressure, Palm.