I've been using the MacBook Author app to do a little publishing to iBooks on my iPad and am completely impressed with the ease of authoring and the power of rich media support in it. Apple has established a framework with iTunes U that supports the educator and student and I believe that it fits the horizontal and vertical integration model that had lead to the substance of their success. Apple will now allow individuals to set up their own course offerings in iTunes U and that will lead to the average person not only being able to self publish but will lead to individuals doing their own courses. There are pros and cons to this as with everything else but I'm certain that traditional brick and mortar institutions are concerned and what this will lead to. The best example that I've seen of this is from Stanford for their iOS development class (2011 version). It is a perfect example of all of the course material being accessible on demand including video of the class sessions, all slides presentations and tests material. The course in iTunes U is a very well organized structure and I recommend it for both the content and the standard that it has set.