Not a huge signing that will shake up the landscape of the NFL by any means, but it was a quality pickup to add depth to a group of young CB's that needed some veteran influence.
Stanford Routt and Chris Johnson will most likely start the season as the 2 CB's, but Sheppard gives Oakland a nickel back. Sheppard is a 2-time Pro Bowler who is more than capable to step in and start in case of injury if Johnson is not ready the first game of the season.
He played in 13 games last season with the Vikings. He had 18 tackles and 4 PD in limited action. He only started 2 games for Minnesota.
In 2006, he made the Pro Bowl with the Philadelphia Eagles. His stats were pretty impressive that season: 30 tackles, career high 19 PD with a career high 6 INT's.
No, it won't shift the balance of power in the West, but the Raiders just got a little deeper at a position they were vey weak at.