Sometimes I really miss Jaiku. There you could add multiple streams to your feed, but when following, could also decide to follow certain streams, or not. So I could follow someone's post, but not their flickr pics or delicious bookmarks. Comments on a post where separate from posts as well. Twitter makes this all one big mess. Let's hope annotations will be used to add this filtering (although I haven't seen post client, which is an annotation as well, used for this).