My server has 0 ping a lot. At least thats what people who join my server tell me. I also get 2-20 ping a stuff load, every person seems to tell me "Wow, your ping is 15! I must live in the same house as you" and then they leave. :(
My ping is better than all of yours. It says Dead :D
Ping might be affected by how close you are to the master server.