I really enjoy getting comments on the posts here, and I remove nofollow from the comments because I think people that comment should have some link love. One of the other reasons I enjoy comments is to get to know people and have conversations with those that do take the time to comment.
Things I dislike about comments. People that stuff the name field with their keywords for their website. I know I have let some of them go in the past, but I dislike the top commentators list being stuffed full of keywords, so you have a choice. You can use your name or nickname and have your comments approved, or you can use your keywords and take your chances that I will either do one of two things. Mark it as spam and delete it or I will edit it and make the name field Anonymous. What I do will depend on how good your comment is and what kind of mood I am in.
Also I blasted Blogger earlier in the week for the mess they made their commenting system. Well they have redeemed themselves somewhat. They have allowed links to websites again using OpenID. It is nice to see OpenID getting more attention at Blogger, just to bad they made such a mess of communicating what they were doing. No surprise there I suppose. Google/Blogger are not great at communicating to users about upcoming changes until they come out. The instructions for OpenID are still a little confusing, but it is possible to add a link to your website or blog when you leave comments on Blogger blogs again. Read more about it on the Blogger Buzz blog post.