PageRank Sculpting Isn’t Dead But Comments Can Kill Your PageRank

This post was originally titled “Is PageRank Sculpting Dead & Can Comments Kill Your PageRank”
Following a confirmation post from Google’s Matt Cutts today, it seems PageRank Sculpting as practiced by many SEOs is effectively dead, and comments, even using links with nofollow CAN have a negative effect on the amount of PageRank that can be passed on to your internal pages.