I find that links from actual forum posts rather than forum profiles are much more valuable, and much more likely to be indexed. If you are willing to invest some time, you can quote a previous poster, post a generic yet somewhat relevant reply, and modify the original quote so your link is nestled within the body of the quote. I find that very few moderators catch on to this, and it allows you to get long-term links in otherwise clean forums, which are generally higher PR and more trusted by Google. My only question is, will G catch on to these modified quote boxes and flag this as deceptive behavior? I know G isn't fond of invisible links, but this isn't quite as sketch. I know G also isn't fond of sig links, which these are not. Before everyone tells me I'm wasting my time on these forum links, less than 100 of them have allowed me take #5 in less than a month for a keyword that fetches $5 per click on adwords. And I've managed to stay at #5 for 2 months with no obvious link dilution and drop off in SERPS. It's been a real triumph of keyword research and scoping out weak competition. Now that I've kicked a real link campaign into gear, I expect to see #1 in no time.