To install Sharepoint 2010, we need 64bit machine. This is the general system requirement by Microsoft. I came through a article
In Sharepoint 2007, we have an option to Edit the List items using “Edit in Datasheet” menu in Actions menu. In Sharepoint 2010 also we have the same functionlity. But if you install 64bit office 2010, this option is not supported. You have to install 32bit Office 2010.
This is the great disadvantage. They have mentioned as a disadvantage in the MSDN site too.
Click here to check the MSDN link.