This is a list of unlockables from the beta version of the game.

Beta Tester Medal - Finish one match in the Beta.
Flaming Gnasher Shotgun - Finish one match during the week of May 9, 2011.
Flaming Hammerburst - Finish one match by April 24, 2011.
Flaming Lancer - Finish one match during the week of April 25, 2011.
Flaming Sawed-Off Shotgun - Finish one match during the week of May 2, 2011.
Gold-Plated Retro Lancer - Finish 90 matches in any game type. To unlock in the retail version, score 100 kills with the Gold-Plated Retro Lancer during the Beta.
Thrashball Cole - Finish 50 matches in any game type. To unlock in the retail version, complete 10 matches as Thrashball Cole during the Beta.