I can't find anything about why I would want to use it over any of the hundreds of other testing frameworks out there. How does it compare to xUnit? Is it even the same type of thing? Do any of the links lead to non-trivial examples?
TAP isn't a framework, it's a specification/protocol. Sort of like how HTTP isn't a webserver, it's a protocol that a webserver can speak.
TAP is more about the question of "how does a test suite report success/failure to whatever launched it", and all it describes is what the test-suite should report on stdout. It doesn't offer any opinions about language or implementation.
