The current 5.x release of Battlenet launcher has given many linux wine users a headache with some suffering a white or blank/black screen.

FIX:
winecfg

1. Under the Applications tab click ‘Add application’
2. Browse to ‘program files (x86)\Battle.net’, or wherever you have battlenet launcher installed, select ‘Battle.net.exe’ and click ‘Open’.
3. Back in the main window ‘applications’ tab, select the new entry ‘Battle.net.exe’.
4. Below, in the ‘Windows version’ dropdown menu select ‘Windows XP’
5. Click ‘Apply’.

Blank screen problem should now be fixed.

PERFORMANCE:
For better performance of WoW, there are 2 methods, one is to use opengl and the other is to use D3D9 but using a small trick to provide much better performance. Opengl works fine and provides much improved frame rate without any further messing about, but you might not like the visuals. Regardless, the first step to either method is to first switch WoW to using opengl mode.

Using gedit or notepad open the ‘WTF\configure.wft’ file in the World of Warcraft folder and change the line
SET gxApi "D3D9"
to
SET gxApi "opengl"
and save.

Try WoW now. You might need to set your resolution and full screen mode again. Your frame rate should be much improved, as good, if not better than if you were using windows.

if you don’t like the changed visuals you get in opengl mode and want the nice shiny D3D9 look without sacrificing too much performance.

After first making the change above,

1. Set your in game video options as you like.
2. Restart the game.
3. Use the in game system menu -> Advanced and set the Graphics API to ‘DirectX 9’.
4. Restart WoW.

Now you will have slightly lower frame rate than opengl mode, but much better frame rate and the improved visuals of D3D9 mode than you did before the switch to opengl.

!!Important!!

Apart from setting your resolution and window/fullscreen mode DO NOT change any other video settings. If you do your frame rate will drop substantially and you will have to repeat the switch to opengl and back again.

To get the best visuals V performance you may have to change video settings then switch to opengl and back to directx 9 untill you find the best settings for you.

Also worth a try is replacing Wine 1.7 with Wine-staging. This offers better performance out of the box and the above works for even better frame rates. However; this version of wine is aimed at gaming so may well break any other applications you are using wine for. If you are going to try it out, once installed use winecfg and go to the staging tab. Tick everything.

Before doing your first winecfg it might be worth making sure you already have:

sudo apt-get install winbind libp11-kit-gnome-keyring:i386 p11-kit-modules:i386