Apple has updated iBooks iPhone app to iBooks 1.1.1 version which includes some enhancements, new features and bug fixes especially the support for books with audio/video material, and PDF documents.
New Features of iBooks 1.1.1:
- Double-tap an image within a book to view it in greater detail
- Experience books that include audio and video
- Enjoy substantial performance improvements when reading PDFs
- Look-up definitions to English words inside books without a specified language
- Addresses an issue that may have caused some book downloads to not complete
- Includes many stability and performance improvements
The iBooks 1.1.1 iPhone app is free for iPhone, iPod Touch, and iPad running over iOS 3.2 or later. You may grab iBooks 1.1.1 app via following iTunes link.