How Secure Is Microsoft's Fingerprint Reader?

Moos3d asks: "I recently found out about this Microsoft Fingerprint Reader at the library and ever since then I have been fascinated by using something like this for my own PC. How secure is this compared to using multiple 10+ character long passwords? Some people I've talked to seem to think it isn't safe at all and some people seem to think it is only safe for casual use. I only plan to use it for online forums and other applications that don't require great measures of security so it seems to be perfect for me, but how secure do you think it really is?"