(I'm new to this Google Plus thing.)
I've been thinking a lot about microdata lately. One of the things that bothers me: microdata very much encourages authors to use a single vocabulary. Combining vocabularies is difficult and often requires repeating content. This drives authors to schema.org
because it is the one vocabulary that Google supports.
Schema.org is a closed, proprietary play. It is unclear how design decisions are made, who decides about extensions and changes, what one would have to do to get one's input listened to.
But because of Google's market power and the single-vocabulary issue, others don't even need to bother trying to define new vocabularies overlapping with schema.org
. It's hard to see how other, better or more open, community-based alternatives like microformats could ever develop.
So I wrote a blog post today about how microdata could be extended to better support multiple vocabularies. It's not as simple as I'd like; I can definitely appreciate the technical reasons for restricting microdata to a single vocabulary per scope … Anyway, the link is below.