What it will do:
It is alternative option for Google Documents. You can edit MS office products like Excel, PowerPoint, Word etc., in browser. You won't have MS Office applications like Access and Outlook though.
How it Works:
You need NOT have MS office installed in your Desktop or Laptop and no need to worry about version of MS Office. You can store documents in Windows Sky Drive (Storage space of 25 GB is free) and you can edit them over browser.
When it is coming:
It is coming in First half of 2010. Beta version is available for Windows Sky Drive users.
What are the Features :
The Office Web Apps are being certified to work in Internet Explorer, Firefox, and Safari
Sharing and collaboration made possible though this, editing documents over online for free.
MS office web version provides close look and feel of MS office desktop based version.