Originally Posted by nekrosoft13
Vista Second Edition basically.
best clue is the is Server OS.
Server 2008 based on Vista Sp1
Server 2008 R2 based on Windows 7
They basically had to change the name for consumer level OS because of rather lower intelligence* of general consumers, and initial bad publicity around vista.
They are actually just staying consistent with their naming conventions - it was the same way for Windows Server 2003.