Would GTR2 system work,1 user 1 key for online ,not sure that any method will stop offline usage.
Steam is a good option for digital distribution,however i dont like the way that a person can loose access to all their games
just by logging on to a hacked server as happened earlier this year in Modern Warfare,even though the decision was reversed
after a couple of weeks(took a lot of complaints), so id be against their game server protection.
Also I do like having a physical dvd though ,in a nice box with a manual that i can read without having to sit at the pc,
(like the old days of Diablo etc) when they were works of art in themselves
Maybe im old fashioned in that but the dvd case is just sterile.