Very interesting post! I've seen some websites that have been selling Reddit upvotes in the past, and since that time I've always been skeptical at the content that actually gets upvoted to the point where it reaches the /r/all or the frontpage. I think Reddit has got so big that many people or companies are doing this regularly, but at least Reddit seem to ban the people they find out about.

Anyway, thanks for posting this analysis of the "Addit" situation :)