Can having a lot of incoming links from only blog comments to a site that is not a blog become an issue for ranking? Let's say I have a website about building your own house. I get blog comment links from blogs that talk about fixing drains, repairing the stairs, etc. What I am wondering is, it is good time spent to get a good number of such comment backlinks? Or, is it better to get links from business directories and other types of websites? I'm basically trying to find out how much Google values backlinks from blog comments, compared to other types of backlinks.