i think you can get more backlink rather than only focus on forum and blog comment. Why not build backlink like submit article, submit PR and exchange link. Remember look for quality backlink rather than quantity backlink .
If you really want high back-links then it's important that you take the time to submit your sites to directories.
hmm, well the article is useful to beginning which is a plus, but I think that blog comments are soon going to mean next to nothing, if nothing already