Hey all - there's been a lot of forward motion for MIDI 2.0 since NAMM.
First, here's a really good overview
about the 2.0 CI (Capability Inquiry) and property exchange protocols. Scroll down far enough, and you reach the bits-and-bytes portion of the spec.
Second, the complete set of five core MIDI 2.0 specs will be available before the end of February. To download them, you'll need to register as a member of The MIDI Association, but it's free and there are no strings attached - you don't have to be a developer or manufacturer to get the specs.