Well, we have confirmed RapSheet's report. It is a torn bicep, but no details on how torn or how long.

Tom Silverstein ‏@TomSilverstein 16m
Just confirmed Raji tore his biceps from a league source. Fear is it's season-ending.

Jason Wilde ‏@jasonjwilde 22m
Not that you should ever doubt @RapSheet, but source says #Packers are indeed afraid Raji tore his bicep. Worried last night. Carry on.