With meta tags you have to ask "what uses it?"
I've never even HEARD of "distribution" as a named type, and as such I've never heard of anything that actually would make use of it. Sounds like more of the useless bloated garbage sites like metatags.info want people to add to their page for NO GOOD REASON.
Since there's not a single piece of software out there that makes the least bit of use of 90% of the trash they promote.
the two http-equiv= : content-type and content-language
the two name=: keywords and description
and MAYBE name="robots" for values that are NOT the default
Anything else? COMPLETE AND TOTAL WASTE OF TIME.
Well, unless someone screws up your site by filing an ODP without your permission... then the 'noodp' googlebot one might be useful.
But Author? Generator? Rating? Trash, don't even waste your time.