R-A:
I have found the 'hide' function particularly useful for people who update with stupid statuses but who I don't want to cull for whatever reason.
Same here - there's one guy who basically cuts and pastes his Twitter updates into Facebook, which is monumentally irritating, but he also makes sensible comments on my various posts, so hiding his status updates solved everything.
But he's the only person I've blocked, as for the most part my friends' status updates are great, ranging from genuinely interesting to intentionally funny to barking mad. I suspect the fact that the vast majority are writers and assorted meejah people probably helps.