[*]this will get the high-priced college textbooks cut down to dirt cheap prices. Why? Because the publishers who enjoy the fat profits on those textbooks will choose to cut their profit throats to help Apple sell more Tablets?
As a retired college professor, I do want to comment on this point. "Textbook" has multiple meanings. The biggest bucks are in the traditional Intro texts in the social and physical sciences (now edging above $100 per text, and even more in the physical sciences). Increasingly, they are revised annually, to cut into the used book market, not because there's sufficient change in the science to justify such frequent revision. This results in extra costs, both for the editing (and don't forget all the supplements--work-books, student guides, etc), and for the press runs. DRM will cut heavily into the resale problem, and may thereby reduce the cost factors I've just listed.
Then there are the other required texts: "readers" in all fields, crucial upper-division books--novels for English, and classics in various fields, etc. Again, if DRM cuts into text resales, publishers will have increased volume.
Then there are the positive advantages of tablet-oriented textbooks--hyperlinks, the ability to annotate (marginal notes, highlighting, etc.) the ability to link to student blogs (academic, that is, not social).
So?.... Anyone expecting "dirt cheap" e-texts will be unhappy with what the market will actually offer. But e-books could be somewhat cheaper because they won't be so frequently updated, and of course they will have neither printing nor distribution costs. (And assuming a 30% iTunes fee from Apple, that won't be more than now goes to wholesale and retail distribution.) And I think contemporary students will really like the utility of e-books of the quality the Tablet will make possible--and being able to carry a two-pound (??) tablet rather than five two-pound intro texts.
If there's widespread production of e-texts by the major academic publishers, college students are going buy Tablets in droves in time for the Fall 2010 semester.