You can move the following file from PC to PC to transfer your Aliases.  Please backup your original file as there is no option for merging, only overwriting aliases at this time.

To access the file, copy and paste the file paths into the "Run Prompt" (Windows Start Button, Run).

The file is located at:

On Windows Vista, 7, and 2008:

%userprofile%\AppData\Local\Microsoft Corporation\MuvAliasSettings\muvalias.xml
or
C:\Users\Username\AppData\Local\Microsoft Corporation\MuvAliasSettings\muvalias.xml

On Windows XP, 2000, and 2003:

%userprofile%\Local Settings\Application Data\Microsoft Corporation\MuvAliasSettings\muvalias.xml
or
C:\Documents and Settings\Username\Local Settings\Application Data\Microsoft Corporation\MuvAliasSettings\muvalias.xml

and can be copied to other computers using the same path.