I have been heavily diversifying my backlink anchor text since penguin hit. As well as using a wide range of sites and types of sites for those links, d0follow, nofollow, low PR, high PR etc etc. Something I've been pondering though is, when I come across an opportunity to place a really high value link to my site, should I use my keyword as the anchor text if possible? Or will I get just as much benefit from just using say, a naked url in that link (as this will inevitably look more natural in some circumstances). So what I'm asking is, if that isn't too clear: Does Google give more of a serp boost for a particular keyword, if it finds a high PR, relevant page with a d0-follow link using said keyword as anchor text, or does it calculate serps based on general anchor text profile regardless of a particular link's value. If that makes sense? Thanks!