Microsoft has made available a product resource guide for PowerPoint 2010 which include several documents in both docx, pdf and xps formats:
- Features and Benefits
- Getting Started Guide
- PowerPoint Product Guide
- PowerPoint 2010 Final Top 10 Reasons to Try PowerPoint 2010
- PowerPoint 2003 to 2010
The documents are available as individual downloads so you can just pick the format you want to download.