I've had that problem when I tried to login with the retail WoW launcher, IceCold launcher works fine though..
However, about the server, I can assure you the raiding is actually really good, and so is the pvp. But the bugs and constant QQ will get on your nerves. The majority of the community are very unfriendly if you're better than them. Let them kill you a few times and they laugh at you, kill them once and they go on about how your class is OP/bugged or about how they have lag etc