The OSX/OpinionSpy/PremierOpinion story has unfolded rather more slowly than we're accustomed to seeing in the world of Windows (where PremierOpinion has been flagged as adware, spyware or "possibly unwanted" for quite a while.
As far as the 7Art screensavers are concerned, the last time I checked, the screensavers themselves seemed to be clean, and allowing access to PremierOpinion was optional. I don't have access to a Mac right now, but I'll check again when I do.
In the meantime, I've added a section on OSX/OpinionSpy to the slow-growing malware information database at http://macviruscom.wordpress.com/apple-malware-descriptions/. It's not a detailed analysis, but it includes several links to much fuller information.
David Harley CITP FBCS CISSP
ESET Research Fellow & Director of Malware Intelligence
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