Pro of hub: You can put it where you want, in easy reach of plugs.
Con of hub: It's just one extra thing sitting on your desk.
Pro of card: It's out of the way, it's attached to your computer.
Con of card: The plugs aren't as easily reachable.
All-in-all, I'd go with the card. I value my desk's real estate and like having as much stuff integrated into my computer as possible. (The days of externals are numbered in my opinion!)