This is a free eBook from Microsoft which is having 258 pages and covers an overview of the Microsoft Office 2010 suites and information about how to get started. Thos document is available in .doc, .pdf and .xps format.
The content includes
Comparison of office 2010 editions
What is New,
What is Removed
Changes in Word, Excel, Power point, Project 2010, Publisher 2010, share point Designer 2010, Visio 2010 etc
Get it from Microsoft