Do. Not. Want.
I don't use it, I don't want it. Nor do I want to be picking up extra work because everyone else is playing fucking scrabble instead of doing what they should be doing.
This might sound old-fashioned, but here it is. A business pays you to do a job. Not piss about prodding people and playing with friends lists. If your business doesn't REQUIRE you to be using FaceAche, there is no reason to be using it. And if a business did require me to register with / use FaceFart, I wouldn't be working there. It's unnecessary and annoying.
If you want to use it, that's your prerogative, but don't expect me to join in, and don't expect me to pick up your slack because you were too busy sending ninjas after your "friends" when you should have been working. What you do in your spare time on the net is entirely your own business, whether it's on FaceBook or YouPorn, but whilst you're at work, you're supposed to be doing what the company pays you to do.
Like adding unnecessary comments to El Reg.... (hey - I'm waiting on some data to crunch!!)