I vote yes.
I'd do bug testing, beta, whatever happened, and doing it by watching 8 vs. 8 bot matches of Brink would be a great way to learn some basic tricks before the game comes out.
I have a bandwidth cap though, so it would have to be a relatively small download, or it would need to come in the mail, or I'm not going to be a part of it.
Well, if this kind of thing is ever done (it's a bit late for Brink) it'd probably be done by some kind of steam-like system.
However, in the modern world of communications, they could easily give a disk even to console players, and then activate this kind of voluntary testing or the game itself, online. Games would have less bugs on release and everybody would be able to play the game from the very instant it was released.