You're right. Although I don't think Microdata is quite important enough to be in the main ten, I should have mentioned it in "All The Others". If you post your comment to the blog I'll acknowledge that there.
The microdata spec is uncommonly level-headed. Devs who are more at home slinging jQuery than they would be writing OWL ontologies could get on top of the spec with little effort.
Efforts like schema.org will only help push microdata into the mainstream.
