You login to the game and see the latency bar green yellow or red Mine been red without fail for last 2 weeks T_T

start -> run -> type 'cmd,' then type 'tracert us.logon.worldofwarcrft.com' and you'll get a detailed list of the hops & latency.

Mine at the moment shows ~2,200 ms, which is I suppose quite consistent with the ~3,000ms I was getting in-game. Using 60.48.xxx.xxx.