Apologies for the non-wow content, but I suspect some of the regulars in this forum may be interested in this (I also put the same info in the "diablo 3" thread on this board's general forum, viewtopic.php?f=1&t=18761 )
For those of you who have the Annual Pass and already downloaded Diablo III, beware that you need to re-download part of it, see this post from blizzard: http://eu.battle.net/d3/en/blog/4410912/
Summary: if you downloaded your european-english or german version of diablo 3 before today, you need to re-download part of it using the downloader from the page linked above!
When you run the downloader executable it will ask you for a directory where to store the installer. Make sure that is the same location as you used before - it will be a quick 50 Mb download then, not the full 7 Gb. (It will quickly scan the 7Gb it had downloaded before, so the progress bar acts as if it is downloading the full 7Gb, but will jump to 99% soon)
If, like me, you forgot where exactly you had downloaded it before: the correct directory to point the installer to is a directory *containing* a directory named "Diablo-III-8370-enGB-Installer". In my case I saw the "Shortcut to Diablo III installer" I had on my desktop was pointing to "C:\Games\Diablo-III-8370-enGB-Installer\Diablo III Setup.exe", so the correct directory to point the downloader to for me was "C:\Games". Your location will likely be different, but this should be enough information to help you find it ...