Apple has released iBooks 1.2 for iPhone, iPad and iPod touch with some swell new features. First, it offers support for full illustrations (you know, just like real books). It will also create collections of your books and PDFs, which is quite nice. To create a collection, simply tap the collections button and choose a name. To add a book, tap Edit and then Move. Move between collections by swiping left and right.
AirPrint is also supported (as long as you're one of The Chosen with a compatible printer) for printing PDFs and notes in books, and Apple has even managed to fit more words on a page by automatically hyphenating text (that feature is restricted to iOS 4.2).