I would like to announce the mitigation to an issue customers may see when they use Office 2010 64-bit with existing or new SharePoint installations. Please see the information below for more.
Datasheet feature on SharePoint not available for customers who install the 64-bit version of Office 2010
Customers using the 64-bit version of Office 2010 are unable to use the Datasheet view of SharePoint lists. This issue occurs regardless of what version of SharePoint the customer is using: Windows SharePoint Services 2.0, Windows SharePoint Services 3.0, SharePoint Foundation 2010, SharePoint Server 2003, SharePoint Server 2007 or SharePoint Server 2010.
The picture below is an example of the experience with SharePoint Server 2010 when you click the Datasheet View button.
The component that provides this functionality is not installed during the setup of the 64-bit version of Office 2010 because a 64-bit version of the Datasheet component does not exist.
Customers using the 64-bit version of Office 2010 can install the 2007 Office System Drivers: Data Connectivity Components to regain the Datasheet functionality when using the 32-bit version of an internet browser.
The resolution is documented in KB 2266203: You cannot view a list in Datasheet view after you install the 64-bit version of Office 2010.