I understand the worry of the community. Change is scary and let's be honest a lot of people have a legitimate dog in this fight. That said I am taking a wait and see approach. As it currently stands it's obviously not ready for prime time. I do feel that in when it finally goes live it will open a bunch of great possibilities. Block level control with attaching meta to a block as opposed to a post sounds interesting to me. It might even be interesting to see custom blocks although it sounds like you will be able to write custom code to control block output. Exciting stuff.

Worst case there will be a mass exodus to Drupal and wordpress and joomla will chill in the corner. I'm still pulling for you WP!