Ok, here is more info: http://thenokiablog.com/2006/12/08/how-to-update-nokia-n73-firmware-to-internet-edition/
"The Nokia N73 Internet Edition contains all of the features of the Music Edition, but the multimedia key in the Music Edition goes straight to the music player. The Internet Edition retains the function of the original multimedia key where you can configure your own shortcuts to applications. They also included Windows Live Messenger and a few shortcuts to popular websites in the Internet folder. Otherwise, same as the Music Edition."
on that link you'll find instructions to change it to the internet edition.
just a matter of changing the product code and updating using NSU (Nokia software updater)