CARE: If you have installed some older version of Microsoft Office, the default settings of Office 2010 beta will upgrade your existing copy of Microsoft Office. So customize settings and install it.
Microsoft released beta version of Office 2010, and which you can download free from the Microsoft website here
Top 10 Benefits of Office 2010 Beta from Microsoft website
1. Express your ideas more visually
2. Accomplish more when working together
3. Enjoy the familiar Office experience from more locations and more devices
4. Create powerful data insights and visuals
5. Deliver compelling presentations
6. Manage large volumes of e-mail with ease
7. Store and track all your ideas and notes in one place
8. Get your message out instantly
9. Get things done faster and easier
10. Access work across devices and platforms
you can read each point in detail here
But more than that you can have a look on What’s New Inside Microsoft Office 2010 which is posted on Digital Inspiration which describes each of the points below in detail.
#1. Save Office Documents to the Cloud
#2. Embed Web Videos in your Presentations
#3. Quick Steps in Outlook
#4. Built-in PDF Writer
#5. Document printing made simple!
#6. Broadcast Slideshows within PowerPoint
#7. Video Editing meets PowerPoint
#8. Distribute your slides as video
#9. Built-in Screen Capture
#10. Outlook gets social