I have been de­lay­ing this func­tion­al­i­ty be­cause I ex­pect­ed it to be hard to do, then... it was very easy! Now you can cre­ate "metafeed­s" based on queries. Here's the first ex­am­ple: "Post.im­por­tan­t==True".

Of course, be­yond a set of stan­dard metafeed­s, a UI to al­low the us­er to cre­ate them will be hard but at least the ba­sic func­tion­al­i­ty is there (BTW, it's 15 (fif­teen!) lines of code)