No, these are not the latest version numbers; they signify which version the shown support is relevant for.
Minority browsers are relevant for showing broadness of support for HTML5, and killing the portability incentive/myth of using Flash.
Market share: I wouldn't believe such statistics, unless I could verify their classification of the user-agents in question. As a Konqueror user, I am so fed up with being incorrectly recognised as safari user.
Complex? Rather oversimplified, I woud call it, because you can't generally say «this browser supports that format». It depends on the codecs shipped with the operating system more than anything else, which this table fails to convey.