Just a passing note about a news story I saw today:
http://abcnews.go.com/US/wireStory?id=10806183
If the majority of the US is standardizing on a single curriculum (or, at least, a standard base curriculum), that makes a nice stable target for Wikibooks textbook authors to aim at when creating books for school-aged US children. It certainly beats the large and unruly mess of competing standards that made such targetting impossible for Wikibooks in the past.
--Andrew Whitworth