Some peolple thinks the comments on blog is not consider as backlinks bybsearch engine. But I think yahoo consider comments on blog as backlinks. My comments on blog was counted by yahoo as my backlinks.
If the post really interest me, and I know about the topic, than I likely to post a comment. Don't post a comment if you don't know what to talk about, make you really stupid.
If the post interested, no matter its low PR or not, I will make a comment or two. No one start a high PR, they have to start with zero PR.
I read blogs like I'd read the newspaper. If I see something in the newspaper that I really like or that is really controversial, I'll say something out loud to the person beside me. Same thing with a blog, except I'll leave a comment. Typically I'll comment on ~10 posts per day, but this is tiny relative to the 500-1,000 that I'll often read in a day. Most readers are the same ... I always expect a 1/100 to 1/1000 comment to reader ratio.
I receive lots of comments and you need to engage the commenters. I've also found that participatory posts and humorous articles extract the most comments. The reason why people don't comment is more profound. Some people feel there are too many comments and believe adding theirs won't matter any. While others never see the comment link at all, lol. Seriously..I have people who commented and said they've been reading for a year and only just saw the comments link.
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