We are in the process of implementing SharePoint 2010 intranet for one of largest EPC company based out of Kazakhstan. The company being an enterprise organization spread across different locations has different version of MS Office tools installed in its employee’s  machines. A question was put up to us to find what will be the support for different versions of MS Office in SharePoint 2010.  This is what we found out from the Microsoft Business Productivity white paper http://technet.microsoft.com/en-us/library/ff384150.aspx 



MS Office Version Support Compatibility
Office 2000 or Office XP Fair Microsoft Office 2000 introduced the first interactions with Windows® SharePoint Services, which provides simple file operations that allow people to open and save documents on SharePoint sites from their Microsoft Office 2000 applications and receive alerts in Microsoft Office Outlook® 2000. Microsoft Office XP builds on this level of data integration to provide interactive access to data stored on SharePoint sites, which allows people to export list data to Microsoft Office Excel® XP and view properties and metadata for files stored on SharePoint sites.
Office 2003 Good Good level of integration with Windows SharePoint Services, and SharePoint Portal Server 2003 which allows users to create documents, organize team meetings and activities, access and analyze data from SharePoint sites, and use Microsoft FrontPage 2003 to customize lists or Web Parts on SharePoint sites. People can also use data integration between the Office 2003 and Windows SharePoint Services to move data to and from SharePoint sites and create databases linked to data stored on SharePoint sites.
Office 2007 Better Microsoft Office 2007 provides contextual integration with Windows SharePoint Services and Microsoft Office SharePoint Server(MOSS), which allows people to interact with SharePoint sites without leaving their Microsoft Office programs, and provides two-way synchronization with collaborative information, documents, and business data stored on SharePoint sites.
Office 2010 Best Microsoft Office 2010 with SharePoint 2010 gives people the ability to view and edit with PCs, browsers, and mobile devices. This combination also includes greater capabilities for people to use Microsoft Office applications to edit documents and work with information from line-of-business (LOB) applications while offline, and then resynchronize when they’re reconnected to the network. The ability to co-author the same document or share a Microsoft Office OneNote® notebook reduces review cycles and enhances teamwork. Microsoft Office Backstage view puts many more SharePoint 2010 capabilities in the context of Office applications, including greater automation of metadata capture and streamlined access to document libraries and SharePoint workspaces.