OK, i know that with my purchase i can let someone else install the game for the use of lan only. So, my question is how do i do that? Does he (in this case my little bro) install the game with the same serial, or is there a code i need to put in so that he can only use it for lan? Can someone clear this up for me?

Also, the serial key i got in the e-mail, is it the same code that will be in my CE that is coming in the mail in 3 days? If it is, how did they know? I wonder if that is the reason people got keys earlier then others because they did the download only compared to the download and DVD.