Players accessing the game through the World of Warcraft Launcher will receive a patch for our launcher and downloader tools. This patch brings the launcher and downloader tools up to date in preparation for background downloading the 2.0.1 patch data.
If you do not use the launcher to access the game you will not be able to use the background downloader and will instead receive the tools update the next time you receive a game patch. It’s necessary to use the launcher in order to receive the tools update and background download patch data.
You may notice that the background downloader is downloading very slowly or that the percentage downloaded is not moving. This is the intended functionality of the background downloader as it is meant to run for extended lengths of time at a slow speed so as not to impact performance.
We do not currently have a tools update for Mac users but we will have one available shortly.
more info about the Background download can be found here http://forums.worldofwarcraft.com/thread.html?topicId=48524887&sid=1...