My brother has the same problem when he is at my parents flat. He also connects wirelessly through their router. Strange thing is, only WoW disconnects, a TS connection stays established though.
When we tried to explore the problem, we realized that the router disconnected after short times of no network activity. We then turned this off, which made the periods between disconnections longer, but the problem persisted.
I still don't know the reason yet and wonder if I'll have the same problem when I go there and try this with my new MBP...