Slimy said:

Microsoft Office 2010 has reached the Technical Preview stage, and Microsoft has announced that free, ad-supported web versions of its key apps are coming soon. Ars takes a look at today's announcement.

Full Story: Office 2010: Tech Preview now, (free) web apps later - Ars Technica

I'm running the desktop version. But it is a wonderful decision from MS an online office suite That is very interesting for me. Save HDD-space etcetera