A quick comment on why I submitted this ...

This will substantially change the way I interact with Facebook Messenger, and irritatingly so. For the past as long as I remember, all of my IM services have shown up in one client (naim; then Pidgin; then Adium). I'll now be forced to either use the Facebook web client (and, in doing so, feed the mis-tuned reward system in my brain that stimulates itself from seeing the notifications icon light up ...) or use a poor approximation of a keyboard on my cell phone.

It's irritating when a service that I use gets shut down. But, the thing that's truly irritating to me is that I don't even have the option of not using it: I'm locked in still by network effects, and Facebook know it.