Is it really comments for me?

I am glad that I have some basic understanding on the criterias used to rank web pages in search engines. I notice some of the comments were given not because they are interested in the topic. But rather, they are used to link my blog to their blogs or web pages. I did use it once. I find it quite painful to search all the blogs and put in the comments. They must have used a program to do this. Maybe I should write a simple one to do just that.