oooOOOooo! I see a little 'no' symbol (y'know, that circle with a slash that reminds me so much of Ghostbusters) on my friends' profiles in the upper right corner beside "Friend" and "Noise."
I'm presuming that means you now can block individuals (one of the features promised by @ello), but I ain't tryin' it. I don't know if it's reversible.
I'm sure, knowing this day and age of confirmation clicks and editing posts, that it's not a one-click-and-you-can-never-go-back thing, but stranger things have happened (like this social network). =)
Go ahead. Block me if ya like. Then see if you can undo it. I dare ya. ;)