Metatags 101: What it does and doesn't do in D7

The module's features are *planned* at this point, so I'll do my best to answer what you're asking.

Does meta tags allow me to import a meta data schema and have it applied to a content type?

I'm not sure what you mean, but we're planning to make meta tag configuration 'exportable' by entity type and bundle (in your case node and node type).

Can I associate fields in a content type as the source for a particular meta tag?

The meta tags are token-based, so as long as there is field token support, it will be possible. See #691078: Field tokens.

Will meta tags automatically query files for their meta data and incorporate it into a node when i upload a file?

Tokens will always be re-processed after something has been updated, so it just depends if the right token is available and you've used it to configure your content or content type's meta tag.

How does meta tags and RDFa in D7 core work together/ Or are they dealing with different tasks?

Meta tags provide information in one location. RDFa provides information throughout and inside the page's markup. See http://www.alistapart.com/articles/introduction-to-rdfa/

Can I require meta tags be completed if they are left blank or a value is unknown at the time the node is created?

Not sure, feel free to file a feature request for this, but my initial thoughts would point to not having meta tags required. By all means a custom module should be able to use the APIs to make them required, but we shouldn't force meta tags on things in the base module.