Looks like brad actually does have a way to let comments flow backwards up RSS feeds so the original place they're posted will see them...
Now it'll only be 10 years before anyone implements it. Or Facebook will never implement it and will kill off all other blogging choices so it won't matter. Naaaaaaaaaaaahhhhh, they set up http://mirror.facebook.net , they're down with the Internet hippie thing ... right? right?