While in an oblique way I can understand the changes that were made, I don't know if I particularly love the transition from "conversation" to "letters on a messageboard". It's definitely not a way that I'm particularly skilled at communicating but I leave it to those who are more vernacularly inclined.
I don't blame you for being discomfited; you get used to an interface, and when it changes you've got to learn it all over again. I had to do the same when I came to the Midnight this afternoon; I thought for a moment that I had punched in the URL to https://bestmotherfucking.website by mistake.
However, I think you're selling yourself short. You're better at "letters on a messageboard" than you think; you've been doing it the whole time without being allowed to realize it. Please bear with me if this doesn't make sense.
I think social interaction on the web has always been "letters on a messageboard" when it wasn't "graffiti on the bathroom wall", and all efforts at threading, reply tracking, notifications, etc. have been efforts to hide this fact under layers of abstraction intended to make the experience more "user friendly". However, I've found that prettying up the interface in this fashion often does more harm than good because it changes the learning curve from a hill to a flat field at the foot of a sheer cliff. (Of course, this is just my own perception as somebody who's nostalgic for the 90s web and retains an irrational fondness for Unix-style text mode interfaces.)
@mdo is just stripping off the cruft and showing everybody how it really works. I think the Midnight is better for this change, but I understand if you disagree.