Every blog seems to have implemented the ol' rel="nofollow" on their comments' names elements by now. What that means is that the old Web marketing suggestion – post lots of comments around the Web using strategic keywords for your name – doesn't do anything anymore. For someone in Web marketing this is rather frustrating, but two years ago when I first saw this being implemented on a large scale it was obvious how necessary it was. That was also the time when Indian/Out-sourced SEO companies were really getting their footing and, well, the low hanging SEO fruit was to be had through blog comment backlinks I guess. On some of my properties I saw comments triple or more, at least 50% of which was all backlink spam disguised as thoughtful rhetoric like "I agree with the author."
I've been thinking about it all weekend as I have two clients that need to build traffic and Pagerank. When I tell them to post comments on other blogs I know that they won't be building PR, but they may get a few people clicking through to their URL if you write an interesting comment. That's a good thing, but is it proportional to the comparatively massive input? I'm not sure yet, but perhaps there is still opportunity in the content of the comment (if content is still king).
I have yet to do a comprehensive look at whether blog tools are implementing rel="nofollow" (also known as rank denial) on links within comment posts. Many blogs still don't tell you what HTML is and isn't okay, or if they're using abbreviated pseudo-code. In the process of guessing which, your comment (50% chance of double posting) ends up looking like backlink spam and we're back to where we started. Since most of these links are the deep-link kind that SEO-ers love and yet will struggle more and more to create, I can only hope Google provides more ranking weight to internal linking structure so that people can be a little more honest about their actual URLs (by posting to their homepage instead of a deep link).
I just found a new rel: rel="external nofollow", courtesy of Matt Cutts' blog comments whose blog I haven't looked at in a while (it used to guide my SEO practices quite heavily). Now I have to figure out what that is.
SEO is still a fast moving game. That said, by following some basic good practices and emphasizing great content, my most valuable Web properties have continued to increase readership despite a sagging topic and regional economy. My PR continues to go up on some of those pages. I guess I'm doing something right. I have yet to incorporate rel="nofollow" however, so either I'm missing out on hoarded PR or I'm just generous.
Back to my clients; they're writing great content, updating it often, yet the traffic just doesn't come. I think there's a great-content snowball effect on their traffic that they're missing out on because they don't have the initial Pagerank or traffic. Solutions? I'm guessing Digg, Reddit, non-spammy blog comments, cross-publishing, adwords... Anything definitive out there? Other ideas?