From the Website:

Central Desktop for Office enables multiple users to simultaneously co-author Word, Excel and PowerPoint files in real time, eliminating the need to upgrade to Microsoft SharePoint/Office 2010 for the same functionality.

I am pretty surprised that it took so long for this to come to Office. Looks like it could be pretty neat for those that need this level of collaboration. I would think though that their user base is very limited in size. Be sure to check out the video for a better understanding of what the software allows.