This presentation "Bling your Blog" was presented at TCEA. You can find it and more on the presenter's library blog. It has some great ideas about how to boost your readership and get more comments from students.
Cool Cat Teacher's "How to Comment like a king (or Queen)" had some good tip. You definitely see a lot of "Darth Commenters" out there. Thankfully you have all been nice so far! I don't understand how people can be so mean!