Update May 24, 4:30PM PDT: Apple has now posted a support article on its website: How to avoid or remove Mac Defender malware. A note at the top of the article says:
In the coming days, Apple will deliver a Mac OS X software update that will automatically find and remove Mac Defender malware and its known variants. The update will also help protect users by providing an explicit warning if they download this malware.
How is Apple responding to the flood of customer calls about installations of the Mac Defender malware?
According to multiple tech support insiders, the company has doubled down on its policy of denying any help to affected customers. Meanwhile, despite evidence that a large number of customers have been affected by this issue, Apple has made no public statement and did not respond to two requests for comment.