My Prediction, Palm: Pain.

Palm lost about half a billion dollars in market value last week after the company warned of a nasty revenue shortfall. And it seems that was only the beginning of what may prove to be a long and painful decline. Investors brutalized Palm (PALM) Thursday, slashing nearly five percent from its share price, dragging it to $5.98 from $6.26.

$5.98 per share. A year ago Palm’s stock was trading at $18.09. Now, analysts like Matthew Thornton at Avian Securities are saying they see it falling to $4–at least in the short term.

Lousy sales of the company’s webOS smartphones have clearly undermined Palm’s efforts to regain its former glory. With the mood on The Street this dark, you’ve got to wonder if anyone believes that’s even possible anymore.

UPDATE: Here’s a bit of good news for Palm. At the Game Developers Conference in San Francisco next week, the company plans to release its webOS Plug-in Development Kit, a set of tools that may spur development or more, and higher quality, third party apps.