Is the little light on showing that it is charging when it is on? If it is, try shutting down the laptop properly...remove the power plug...remove the battery and leave it sit for about a minute. Do not insert the battery and start it back up with only the charger...boot to the desktop. Turn it off again and insert the battery. reboot. Check if it still exists. If it does it may be a software problem or a hardware problem. You would have to talk to customer support after that but they wont help you since Windows 7 isnt released yet, especially if you have RC.
Let me know what happens.