Need a bit more evidence that the e-book download business is a whole lot different than the music download business? Then look no further than Barnes & Noble, which has just announced that it plans to make its B&N eReader app available for the Apple iPad "around the time" of the device's launch. Details are otherwise a bit light, but the app will be free, and is apparently "designed specifically" for the iPad, giving you access to all of the books, magazines and newspapers available in Barnes & Noble's eBookstore. Could a Kindle app be far behind?