The problem here is that some of the classes use the beta versions of the next edition of the books before they are printed in bulk, so there are multiple versions of a given book floating around. For instance, in the Berkeley class a few years back, they got an updated version of the verbal book that was being editted and revised that makes up the current book that every location and homestudy now uses. They collected data on the questions and made changes to questions based on the feedback. Once they have revised a book and it has been through the classroom feedback cycle, then it gets printed.
The homestudy versions are the latest finalized editions. At the moment, the new physics book is on the verge of being finalized, getting its last cycle of beta testing with the current Irvine and Westwood classes. The physiology book is being written and editted by Berkeley people, so the Berkeley class will be using the editted version of that book this year.
This means that there are multiple versions of each book floating around, and the latest edition can be ascertained from the copyright year and printing format. The odd binding means it's the latest edition in progress and regular binding (with glossy covers) means it's a main printing. Except for general chemistry, 2008 is really close to 2009 and 2010 versions. For general chemsitry, the 2010 version has come changes in a few chapters.
The 2010 physics beta version is different from the 2010 finalaized version in that it has a different layout for the passages (instead of phases, it has a 25-question review exam and a 52-question practice exam), contains some new passages (three to five per section), and has answer explanations to the B questions. There are also some new test strategies and tircks included too.
