Regardless if people want to accept it or not, banner ads can contain spyware. I have tested this, and reformatted a hard drive, installed the program in question and as soon as banner ads appeared, the virus came and my firewall program and anti-virus programs lit up like a Christmas tree. This particular one was so malicious that the only way to stop it was to disable IE. The following day a friend from Thailand PM'd me with the same problem and the same symptoms, same virus.

I am only saying this to show that it is possible. In this case, it's not as severe. It appears to only be a redirect, but keep your eye open. This could be just a test for something worse down the road. Also, banner ads do not represent the site. Fencer cannot do anything to completely stop viruses from leaking through them. If you absolutely do not want any chances of lost data or spyware, then backup any important files and if the paid service here removes banners, you won't get them.

If you are like me, you will fight these nasties as they come and learn the system. If anyone thinks they are infected, feel free to contact me and I can try to help you further or send you to the right people that know more than I do.