Detecting Different Vista Editions

Need a desktop

application to determine the Windows Vista's edition, e.g. whether application

is installed on Ultimate, Home Premium, etc..

Have located this

registry key in the Vista

installation.

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows

NT\CurrentVersion\ProductName]

Will like to know

what is the final product name that will be feedback by this key for the 6

editions that Vista is going to

have?

If there are better ways of detection, please advise.
Any advice is very much appreciated. Thanks.

-Fred