If your resolutions for 2011 include teaching yourself to be a Mac or iOS developer, then Apple just gave you a very nice Christmas present.
According to a tip from our old friend Nik Fletcher at Realmac Software, Apple has recently put a number of Apple Developer Publications books into the iBookstore for free. This makes it simple to grab these books, which range from "The Objective-C Programming Language" to "iOS Application Programming Guide," for reading on your iPhone, iPad or iPod touch.
As our resident developer and iOS guru Erica Sadun points out, it's "kinda dumb" to have the books running on the device you're trying to develop for. It would be nice if Apple eventually made a version of iBooks available for Mac OS X. Although, as commenter Nick points out, once you have the books downloaded, you can open them with any app that supports the EPUB format, like Adobe's Digital Editions product.
You can also get a Mac-compatible version of the books by going to the developer site and then selecting the PDF option to download them. The PDFs can also be used on the iPad or iPhone, but since Apple has done the work to convert these documents into nice EPUB-formatted iBooks, why not take advantage of their effort?
By my count, there are six books available. To grab them, launch iBooks on your device, tap the Store button, tap the Search icon and then type in "apple developer publications." The books range in length from 44 to 200 pages, and they are great references to use with many of the other developer books from Pearson and Peachpit Press that can also be purchased in the iBookstore.