Also interested in this thread, and also heard from my letter-writers that the process was super gnarly. Just had my first round interview last week. Anyone else go through this yet? For me it went meh — not great, but not an unmitigated disaster. Mostly just talked about my research, then stumbled re-deriving a result that I had posted on my research website a few years ago. Oh well. Interviewers were really cool people though, and talking to them was fun.