This is a Facebook scam that’s aimed at people who are hoping to get a free iPad or iPhone by giving their opinion of the iGadget in question. Of course, there are no free gadgets on offer. (Also flagged at Mac Virus.)
Graham Cluley, who flagged this scam, suggests that if you find a message inviting you to take part, that you delete it and change your passwords. He also suggests that you might want to follow the Sophos Sophos page on Facebook, which flags a great deal of the unpleasant spamming and scamming that is spoiling FB even more than the mildly disturbing Mr. Zuckerberg.
I listed some other resources you may also find useful on this blog (which seems to have become more of an all-purpose scam, spam and hoax blog) in the article Facebook hoaxes and scams.