After several attempts to balance the Nitro Boots ability in the arena, we have decided that we currently do not have an acceptable solution. Until we are able to better balance this ability it has been shut down in the arenas. We fully plan to continue working on this item to ensure that it is still worth the investment made in it and we intend to adjust it in upcoming patches.

There is an open thread in the PvP forums should you wish to discuss this change - http://forums.wow-europe.com/thread.html?topicId=9158361169