Blogging laziness. Like he said ==> http://clintboessen.blogspot.com.au/2010/05/how-to-import-nk2-files-into-outlook.html

This is my instructions (just in case the above doesn't google up for me again) for moving from Windows XP Pro/Outlook 2003 to Windows 7 Pro/Outlook 2010

1. Copy the Outlook 2003 <profile name>.NK2 file from the users %APPDATA%\Microsoft\Outlook folder in Windows XP Pro to
   \Users\%username%\AppData\Roaming\Microsoft\Outlook making sure you rename it to be the same as the Outlook profile name on the Windows 7 target machine.
2. on the windows 7 box cd to \Program Files (x86)\Microsoft Office\Office14 and run outlook.exe /importnk2 and your done