The version on github is apparently not the most recent version, which is 2.1. The 2.1 version has support for HTML5 custom data attributes, but with surprising semantics (string values have to be double quoted, with resulting bug reports). And a number of other bugs, all going stale or inundated with spam.

I'd like to help improve the situation, but I'm not sure how to proceed.

EDIT: I've submitted a couple of pull requests on github:

http://github.com/jquery/jquery-metadata/pull/1

http://github.com/jquery/jquery-metadata/pull/2