Just finished reading Jim Baggott's new book called 'Higgs: The Invention and Discovery of the 'God Particle''. The book discusses the recent discovery of the Higgs boson, of course, but it also does an excellent job of explaining the development of the Standard Model of particle physics. The book provides just what the general reader needs to understand the discovery of the Higgs boson and what it all means (but is not dumbed down by any means). I've written an executive summary of the book available at newbooksinbrief.wordpress.com.
Cheers,
Aaron