[sentientbicycle]

"So now textbook authors are forced to license their books in such a manner?" No. This would be much bigger news if that were the case. This is who would make them from the council digest: "The bill would require the council to establish a competitive request-for-proposal process in which faculty members, publishers, and other interested parties would apply for funds to produce, in 2013, 50 high-quality, affordable, digital open source textbooks and related materials, meeting specified requirements." This will enable the exact opposite of your last three conjectures. It will decrease the cost of textbooks, the quality will go up, and we'll have even more options to choose from. Plus this is a big win for other educational enterprises. Under the CC BY license outside industries will be able to utilize the material for commercial endeavors.