From a Zogby International poll of professors funded by the Association of American Publishers (AAP):  Survey of College Instructors Regarding the Use of Supplemental Materials in the Classroom

When choosing which textbook to adopt, do you assign more importance to price, more importance to the effectiveness of the learning tool, or are they equally important to you?

• Effectiveness as learning tool is more important 71%
• Price is more important 4%
• Both are equally important 22%
• Not sure 4%

(Hat Tip: Inside Higher Ed.)