I just joined Blogtopsites.com recently, added this blog to two categories there. Blogtopsites.com do have high PageRank (6). It has many categories from gaming, computer, finance, travel, and etc. I submit my blog to two categories: Marketing/SEO and Web design.
For each category, it will show the blog statistics like Unique Visitors and pageview. It also the rank of every blog by its unique visitor. For the Web design category, I’m currently at rank 15. Although it has high PageRank, it won’t benefit us. They did not gave backlink to our blog. Link to our blog is done by using redirection. Therefore it won’t help our PageRank.
Although it will not affect our PageRank, it sure can give us traffic. Other webmaster and competitor might see the link and visit our blog. You can learn from other blog, because you will know which blog has high traffic. Visit their blog and learn what do they have in their blog.