Fortunately, this isn't the case anymore. Any type of dangerous tackle like that is sin binned or red carded directly. Even in big games. I think the welsh captain was sent off in the first 20 mins against Australia, semi finals... I'm sure someone on here will know the exact game date and time...
Has it been decided?
I still think that is low for the challenge. I know you can't compare other sports directly, but I'm sure with rugby that it is almost a season ban for such an incident.