Whoa! Here at the former GeoNet, the Community UI booted me right out and required my signing in again. Naughty, naughty! Aside from that, my favorite DevSummit streaming peeves: buffering, buffering, dropping out, skipping, etc. I totally dropped connection twice so far. On the other hand, I am glad that I could download slide decks right away (ahem! only for certain sessions).
Push comes to shove, this is no replacement for the real thing. But I commend the Esri staff for doing what they can.