Neutron certainly looks very promising - assuming the performance translates across all forms of objects, which I'm going to assume, it would be crazy otherwise. The only frustration is that it still looks like it will be another 12-24 months before this moves from 'technology demo' - fun to play with, but not much use - to production ready. I hope it's sooner, but reading between the lines that's my feeling.
Looking at Rick's demo, I think the only node in the geometry listing was 'sphere' - so I expect we're going to see a lot of dancing balls in a few months time. Ho Hum.
For me the immediate highlights are the near term availability of Redshift OSL and Redshift RT. Also excellent to see support for USD.