OK, this does look like the first proper Mac OS X virus / trojan thing; that in itself is tedious and a shame. However, I don't suspect this is going to affect many people and hopefully Apple will grab the bull by the horns and issue a quick fix. In the meantime, check out the link on how to protect yourself.

BBC NEWS | Technology | Malicious worm aims to bite Apple: “Mac users are being warned to be on the lookout for what is being called one of the first viruses for Apple computers.” (Via BBC NEWS | Technology.)

How to protect yourself against the latest Mac OSX Trojan/worm/“virus” from Guardian Unlimited: Technology: “There's been a lot of discussion following the discovery of a bona fide worm for OSX - ”Leap-A“ or perhaps ”Oomp-A“ (depending which AV firm's deconstruction you read) - which spreads via iChat and tries to spread via other methods too.” (Via Guardian Unlimited: Technology.)