Though the native apps are the bread and butter of the iPad, it's the new iBooks app (and semi-associated interactive magazines) that will ultimately drive the potential success of the iPad. Apple has every intention of making the iPad to books, and publishing as a whole, what the iPod was (and is) to music. Given this fact it seems odd that iBooks isn't installed as standard, instead it's a free download from the App Store that comes with a copy of A.A. Milne's, Winnie-the-Pooh.
Nonetheless it's an essential download, as the application itself is simply outstanding. Not only is it visually charming, arranging books into a virtual bookshelf and mimicking the look and feel of a book, it's packed with attention to detail that makes it a joy to use. Small things, such as the counter that tells you how many pages remain in a chapter, are great touches, as is the ability to quickly look-up dictionary definitions and search Wikipedia and Google straight from the app. Such features add a level of depth and sophistication missing from eBook readers like the Amazon Kindle and the Sony Reader PRS-600 Touch Edition.
Accompanying this is the inevitable iBookstore, which is pretty similar in format to iTunes and the App Store. Buying books is very slickly handled, even allowing for reasonable size samples to be downloaded before you decide to buy. At this point, however, the weakness of the store is its library. Official numbers suggest a catalogue of 60,000 books, of which around half are from the Project Gutenberg free eBook service, but independent assessments suggest the figure is closer to 45,000.
In either case it's a far cry from the 500,000+ books currently on sale on Amazon's Kindle store, so Apple has a long way to go before it becomes anything close to comprehensive. Of course Amazon has its own Kindle application for the iPad as well, so it's not a pure either/or decision, but the Kindle application isn't anything like as polished and enjoyable as iBooks is.
Another question is whether the iPad is the right kind of device to read books on. Compared to eBook readers and their paper-like displays, it's difficult to read on the iPad in bright sunlight unless it's at full brightness, and even then there are reflections and fingerprints to distract you. eBook readers also benefit from battery life that can be measured in days rather than hours, though the iPad doesn't do too badly itself. Really pummel it and it will still go 10 hours or more before a charge, while more real-world (semi-regular) use should ensure battery life approaching 24, 36 or maybe even 48 hours at a push.
Finally, there's also the question of eye-strain to contend with, since a backlit LCD will unavoidably put strain on your eyes over a prolonged period. Reading for just an hour or two is unlikely to be a problem, but more prodigious readers (and anyone who's more sensitive to such issues) may disagree. You'll want to purchase a case for your iPad, too, since the smooth aluminium back makes it slippery to hold.
So the jury might still be out for reading books on the iPad, but there's no doubt that it could herald a whole new lease of life for magazines and newspapers. There are various examples of dedicated apps, such as USA Today, Popular Science and the Zinio viewer app, which demonstrate the potential. By far the best example, though, is Time magazine's dedicated app. It brings the magazine format into a completely different, interactive light that showcases the potential for media designed specifically for large-format tablets.