Lots of mention of Semantic Web in Data.gov ConOps. I'll read it in detail on the plane . . .
Dean Allemang and Jim Hendler: Semantic Web for the Working Ontologist: Effective Modeling in RDFS and OWL
Latest book by Dean Allemang and Jim Hendler. Aimed at people who wonder what the Semantic Web is all about, but who don't want to have to learn logic. It is still a technical book - you'll learn what the standards are and how they work, but from the point of view that someone who is technical in some other field (say, biology or astronomy) could use.