Has finally woken up to the problems being caused by this malware, as a result Apple has released a technical support document, the document goes some way to explaining that you should not enter your credit card information!!, but it does also detail how a user may remove the malware, you can find the document here: removing Mac Defender
Look, Everybody with a mac
Do yourself a favour go over to the sophus website, and download their free antivirus program: Free OS X Antivirus.
Whilst it may not be the best AV on the market, it is going to be better than a poke in the eye with a sharp stick