On the semantic-web@w3.org list, Harry Halpin makes a good case for why attempts to standardize on a Unified Formal Ontology (UFO), such as Cyc and DOLCE are ill-considered. Harry provides lots of literature. Hard to argue with that.
I just don’t want people to think UFOs are a good idea without knowing there is almost 40 years of well-respected people saying they are a genuinely bad idea. And that most foundational ontology/KR based companies minus Cyc more or less crashed and burned in AI Winter, a sort of analogue of the dot.com crash. Feel free to try again, although currently venture capitalists are more interested in tagging than ontologies. I also feel like occasionally UFO advocates pretend to represent the mainstream of academic AI and philosophy, which is not the case.
The basic point: Build the Semantic Web bottom-up, starting with concrete ontologies for specific domains.
(You can’t build complex systems, unless you have unlimited funding and dictatorial control. In a marketplace, complex systems must be grown.)