The popular view is that it does. But do we know of any testing that's been done?
The best way to ask this rather comprehensive question is, I think, for me to put the following list in order from the WORST AT THE TOP to the best at the bottom.
Do you agree/disagree? - and why, please.
WORST = posting non-relevant comments to non-relevant blogs
I have in mind comments like these:
you really made me think.
i'll be back to read more later.
love your template.
my friend told me about your site.
thanks for that.
Question: Does this produce a negative response from Google OR no response OR some benefit?
BETTER = Finding any blogs that accept comments (they dont have to be relevant to your topic), then posting considered and well-expressed comments that actually respond to the original poster's content.
Let's say you have a weight loss site and I have a dog site. I visit your weight loss site and post a useful response to some weight loss topic you've addressed but my author's link goes back to my dog site.
BEST = Finding blogs that are relevant to the topic of your site (the one you want to link back to), then posting considered and well-expressed comments that actually respond to the discussion.
MY CONCLUSIONS SO FAR
1, the higher the quality of the COMMENT, the better
2, the higher the quality of the BLOG, the better.
3) the more RELEVANT the blog is to the theme of the link you are posting, the better.
Or is that too simplistic? -- Because of real world time constraints, and considering that automated or semi-automated commenting software is so much faster than doing the whole thing manually, perhaps it has a contribution to make??