On Wednesday, Apple posted an updated version of the iBooks app for the iPhone, iPod touch, and iPad on its App Store mobile bazaar. 

The free program now supports iOS 4.2′s AirPrint technology for wireless printing of notes you’ve written in iBooks and PDF documents to select HP printers that support AirPrint technology. As you might have imagined, e-books won’t print due to copyright restrictions.

The software also supports fully illustrated books made available in the iBookstore, shown at the bottom of this piece. Here’s a blurb related to this feature straight from Apple:

Experience fully illustrated books, from children?s picture books to beautifully designed art books, available for download in the iBookstore.

Those who manage a lot of books on their device will be pleased to know that the updated iBooks app now sports an improved organization of e-books and PDS into personal Collections. You simply swipe left or right to jump between Collections, Apple wrote in release notes accompanying the download.

iBooks now fits more words per page by automatically hyphenating text, another enhancement stemming from an improved layout engine available only on iOS 4.2 or later.