More Radio Goodness
I wrote my own comment system that I'm quite happy with, so this doesn't quite effect me. But the cool folks at Userland have updated Radio so that you can now have comments attached to posts. It's actually not that bad a setup. I don't think it is quite as full featured as some of the comment systems out there (It doesn't seem to show how many comments there are), but this is a good first step.
While in some cases just linking to someone's article in your own blog and commenting on it can give some response, it doesn't create as much of a sense of community. You may have some interesting little tidbit of information to add to someone's post. Maybe you can correct some faulty information. Definitely a cool move!