Vote for PST Importer 2010
PST Importer 2010 eliminates the need for administrators to manually collect PST files and import them into Exchange 2007 and Exchange 2010 mailboxes. The process is fully transparent and works in the background, without disturbing the end user.
PST folder structure is preserved, and you can choose to integrate archived messages directly into users' personal Outlook folder lists, or keep them in separate subfolders for easy reference.