Niner since 2012
The Mansion demo was pretty impressive. It ran super-smooth (60fps) even on my 4 year old laptop.
Make sure you check out the cemetery: RIP In Loving Memory IE6, Schrödinger's cat, Clippy, and Hamlet.
Nice video on SignalR. It's actually kind of cool to put a face and voice to David Fowler. We've chatted a lot on both NuGet and JabbR.
I'm very excited about the types of apps that a library like SignalR not only makes possible but how simple it is to do so.