There is a on-going argument whether you should make your blog dofollow or nofollow but it is clear that both options certainly have its positive and negative points. Those who are still in confusion, I have tried to point out both parts of making a blog as dofollow blog.
Advantages of Dofollow Blogs
Get More Comments
People love dofollow backlinks and it is likely that you will get more comments when you make your blog dofollow. People will likely to visit your blog often and comment!
Dofollow blogs get more share by bloggers to be followed and commented and as a result generally draw more traffic when it was nofollow. People sometimes generate dofollow blog list and chances that your blog also get listed there!
People would love to subscribe to your blog since they will get regular update of your blog and can visit often to make comments and generate more backlinks.
When your blogs are featured as dofollow blogs in the lists, you will have the possibility to generate some backlinks from it.
Disadvantages of Dofollow Blogs
Increase Comments Spam
Dofollow blogs surely generate backlinks and this is why spammers love dofollow blogs to get such valuable backlinks at ease. Read my earlier post on how to reduce spam comments to fight more efficiently with spams.
Giving Link Juice
When you are giving a backlink to other blog(s), you are giving the blog a vote and when you are giving that a link, you are passing your Pagerank to that. Such links when in huge number might look spammy to search engines.
When you are looking for a good PageRank then making do-follow is not a wise decision. It is not certain that you cannot get a good Pagerank with dofollow blogs, but for this you might need more time and effort to achieve that Pagerank than with nofollow one.
When you make your blog dofollow, you need to choose something between more visitors and comments and losing Pagerank. What is your choice? Dofollow or nofollow?