Google's Matt Cutts released a video about spammy guest posting
. Nothing we haven't heard before, I don't think. Basically, don't keyword stuff "cheap viagra" links in a guest post on a blog about furniture. Keyword heavy linking is obviously the new focus of Google's anti-spam efforts. Ironically, I imagine that's a product of it working more than they would like. At any rate, if you're not operating a pump-and-dump site, you should already be taking relevance and keyword density into account when considering your link profile in general.... Read More!