I’ve been blogging since 2008. I maintain 55 niche (subject specific) blogs, like this one on work at home tips. I do pretty well on Google Adsense and Infolinks ad revenue. So I spend a lot of time experimenting to see what works well. I always included links, also called “tags” on my blog posts. A few months ago, I quit adding tags. I thought that it might cause problems with Google indexing (my blog earnings had dropped). I cut back and removed some links. Bad idea. Read onLinks, Tags Improve SEO, Blog Hits, Ad Revenue Earnings