Campbell is a very good player, 7.14 is probably more than he's worth, but Chicago wanted him and were willing to overpay to assure his signing. Kind of reminds me of when McKee received 4 mill from St. Louis, they definitely overpaid, but wanted to make sure they got him.
Campbell overall is very good with the puck, he's consistently able to gain the blue line on the power play, although he doesn't have much of a shot. He lays the occasional big hit, but isn't a real physical player. His main problem is that he turns the puck over quite a bit, which I believe is the main reason San Jose didn't sign him. I hope he does well in Chicago, they have a really nice young team and should be exciting to watch.