I don't mind a lack of comments all that much as I write a history blog so a lot of what I post is informative rather than up for discussion. On the other hand, whenever I ask people why they don't comment they always say that they feel too intimidated, which isn't great.
I used to comment loads on blogs if I had something to say but then fell out of the habit when my Wordpress login fell out with seemingly every blog on the planet so I couldn't use it. I find Captcha type things really difficult as well so avoid commenting on lots of blogs that I would actually like to reply to because the actual logistics of leaving a comment is too arduous.
I'm trying to get over it and back into commenting now, but I have to really want to say something!
Yes it can be a real pain to actually get a comment on someone's post at times. I think I got a bit too obsessed with the importance of comments...especially, as you've all pointed out, that if you're writing about a niche subject then only a few people will really have an opinion on it.
I comment if something resonates with me or if i've enjoyed reading a post. I never comment if there's already 10 plus comment's though as what i would have said has probably already been said. Occasionally some blogs feel so professionally done that i feel a bit to intimidated to comment but it doesn't mean i won't have enjoyed reading it. I love blogs that have an element of self disclosure about them as i like the more personable feel but i think thats just down to my own personal blogging preference. I follow quite a few blogs through my blog roll, i hardly ever buy magazines these days thanks to the fab blogs i have listed
I often can't be bothered to comment on blogger blogs because the process is so long-winded and annoying.
I usually comment if I have something to say, but comments on your blog aren't the be all and end all - I get comments on posts to my FB page and my twitter stream, so know ppl like what I write. They just don't always have something to say about it on the blog itself
Like Violet5 I comment if something really resonates with me and I really have something to say about it, I don't comment for the sake of commenting, I've had the odd one of those on my blog and I could see right through it, it's best to be genuine. I always reply to people who take the time to comment on my blog as well.
I read loads of blogs, and comment all over the place too. Things that make me comment are usually posts that I can identify with, things that relate to me, or things that I have something to say on. Sometimes though I'll read it, enjoy it but have nothing to say on the matter. Doesn't mean I haven't enjoyed reading it, just that I have nothing constructive to say, so just read and run!
I have a blog I dont have many comments - does that mean it doesn't enthuse people? I will comment if something is fantastic or I strongly agree with or disagree with so I dont know- I have tried asking questions on the posts asking for opinions all help appreciated - perhaps we could offer our comments on other blogs?