What consequesences
 

yah i suppose you couldnt download limewire from limewire and then again you couldnt steal limewire pro. im not sure what the consequnces would be

Jeez, and what's with all the other Software companies on this planet? And don't forget the **AA!

If LimeWire has the ability to block illegal PRO downloads effectively they would be immediately sued/forced to block other files too. And don't forget the aspect of "Open Information Sharing" (right, Information and not just File Sharing) -- some organizations/countries may force LimeWire to block political articles and whatnot if it is technically possible. We can even go further and philosophize about freedom and like that! :)