WoW Mob Tagging ?? ! ??

[razer]

So I was wondering is WoW Mob Tagging still in the game? I seen some people on the WoW forums saying that you can still do this and say that people are going to do it for the exp for first 90 ect. Now I also seen it on these forums but can we still do this and is it allowed if so how would I go about doing it.

Thanks