I think Comment Kahuna is a great tool. I have built tons of backlinks fast with it for other sites. I haven't used it on my 30DC blog yet because I am sticking to Ed's material 100%.
When I do use Comment Kahuna I custom tailor each comment though. I RARELY use the same comment twice. I also be careful not to do too many at once. Early on, I was commenting on Wordpress hosted blogs. (Even though they are no-follow you actually get quite a bit of traffic from them.)
If you post more than like 20 comments in an hour the site will warn you that you are posting too quickly. Definitely don't want to get your IP address or username on their blacklist because it is a treasure trove. (Even with the no-follow business.)
Good luck everybody!
