I use this trick all the time in PvP, mainly against rogues. Basically, if you jump when someone kidney shots you or cheap shots you etc, you keep moving until you land, then you're stunned. This is nice in that it puts distance between the rogue, warrior, paladin, druid, etc. and you so that you can sometimes effectively eliminate their damage output in that amount of time, since they spend the 3 seconds or whatever catching up to you. Timing this is tricky, you either have to be able to anticipate it, or else just jump around a lot. Either way, it can help out and even help you win arena games.