Rogue Security Products continue to spread
AVERT Labs shares a good analysis on why many rogue security products are successful in tricking users
Why is Rogue/Fake AV so successful?
http://isc.sans.org/diary.html?storyid=7144
QUOTE: It is obvious that the bad guys are making (serious?) money with this scamming scheme. There are couple of things interesting about rogue AV programs. First, the bad guys here do not use (in most cases) any sophisticated attacks on clients. They instead rely on visitors to wittingly install their "AV program". How do they do this? Through social engineering – they create web pages which are very authentic copy of legitimate screens in Windows operating systems. These web pages make visitors believe that their machine is infected with several malicious programs and that the offered "AV program" can help them clean it