wheel - 5:22 pm on May 24, 2011 (gmt 0)
Getting in content links from relevant blogs I would expect would work well. In fact, removing the word 'relevant' may also work well.
I'm considerably less enthusiastic about getting links from comments on blogs. I think you'll find that for the most part they'll be nofollowed (useless) links.
In other words, getting articles published on blogs may be a viable strategy. Getting comments published on blogs is likely to work less well.