In general the schema markup is great though. It's semantic web stuff done right: It's not hard to implement, it has tangible benefits, and there is proper tooling around it like the schema markup tester. And best of all: While this is mainly about changing how search results look, there is nothing stopping other software from using that markup. It's really one of the positive things Google is involved in.
It's only frustrating if what you want to do is not supported. I'd love to markup my processor and graphics card benchmark results (the ordered result list), but there is nothing in the schema that would allow me to do that :/