The new 4.7.0101 is available ONLY for Windows XP. MSN for other Windows versions is still 4.6.0.82, although perhaps the XP version can be ripped to work on 2K, but we will see...

Download MSN 4.7 Final English (http://messenger.microsoft.com/install/dl.asp?typlang=en-us&typsys=3)
Download other languages (http://messenger.microsoft.com/default.asp?client=0)