Commenting on blog posts is a time honored way of building links. It’s not difficult, just time consuming if done properly. As an example I’ve had around ten comments on one of my recent posts. None of which are genuine, all of which are spam. So guess what, I have not approved one, so all those comments were wasted.
Basically what these people have done is post a generic comment that often not only adds nothing to the conversation but often does not make sense. How can this be? Because they use automated software that just creates gibberish or, they copy and paste keyword text and links into the comment box.
Makes you wonder why they bother doesn’t it? They can hit 1000’s of blogs with this sort of software and some of those comments will stick. Get enough and it will have a slight effect but not a lot.
If you want to make blog commenting work, you need to start with blogs that are relevant or complimentary to your niche market. For example, one of the comments I deleted included a query about where to buy a wedding dress! Second you actually need to read the post and make a thoughtful comment, something that adds to the conversation.
You can disagree (politely) offer a slightly different point of view, you can even agree with some of the content, but it has to go further than ‘nice blog,
I agree with you’. Get into conversation with the blog owner and give value, that way your link is less likely to get trashed.
Besides ten good quality blog comment links from valued sites will do more for your ranking than 100 poor quality ones that only exist because the blog owner doesn’t care.