In general, I agree with what he says but here I want to elaborate a bit on his first rule, because, although quite natural, it is a bit unfair.
The rule goes like this:
What language is this?
When I stumbled upon a tweet with “strange” characters or words I opened that profile and then asked: does she regularly post in this language? If yes then unfollow. Moral: how can I be interested in what is expressed in a language that I don’t understand?
Such a filter could be used in facebook news stream too, and, in general, in any kind of info ‘streaming’ service.
And, of course, I wrote my proposal in English so not to be filtered out by those who should listen 🙂