After struggling for a while with tracking my conversations via CoComment, I've recently decided to switch over to Co.mments. It seems to be working pretty well. I considered a few of the other services as well, but it seemed like they were the best choice.
I'm still not sure that there's a great overall answer to Blog Discussions Types. I discussed the specifics of Blogs, Community and Discussion Tracking - What's Really Needed a long time ago. Not sure that we've got an answer quite yet. It's still very messy to try to track all your activity across the network. Maybe there is no answer given how fluid everything is, but it still would be nice to have something better than what we have right now.