So called because it looks like an Adobe Flash Installer. There seems to be a ton of news around this Trojan on various Mac-related websites. http://www.tuaw.com/2011/10/19/trojan-variation-disables-mac-malware-protection/ for instance.
We wrote protection for this in ClamAV about 5 days ago. I know a lot of Mac users run ClamAV, so I just thought I'd throw this out there.
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