But the experts have to participate. Professors generally review textbooks for money or academic credit. Plus, folks in academia do not like wiki's in the first place, and will not give scholarly credit for promotions/tenure for this work (too bad, it is worthwhile). It seems to me full online textbooks written by a small group of professors or experts seems more likely to reverse the high cost of textbooks. There is a good start at www.textbookrevolution.org with this idea.