Getting an error says battlenet is down cant use OQ.
Battlenet is UP

Open your friends tab by pressing O.
At the top does it list your battletag?
If yes: you are connected to battle.net. Log out and log back in.
If no: you are not connected to battle.net

yes, no it is not listed and yes I AM connected

If you battle tag is not listed at the top of your Friends list (O), then you either:
1) are NOT connected to battle.net.
2) do not have a battle-tag.

Do you have a battletag? Your battletag is different than your realid.

Information on getting a battletag: http://oq.publicvent.org/battle-tag-missing-or-invalid/

I'm getting the same problem. I have a battletag, I have logged out of and back into Battle.net numerous times, but I still get the message from oQ in game that Battle.net is down and oQ is therefore disabled. Everything was fine yesterday. Could it have anything to do with the weekly maintenance that Blizz did earlier today?

Update: Intead of logging out/in from the desktop application, I hit the 'back' button from the character screen in WoW, relogged into the WoW log screen, and now everything seems to be working fine both for battle tag and oQ

It is maintnance day, so there could be some wierdness happening as they update systems. However that is interesting and i will sugges to others to try and run wow from the icon rather than the battle.net app and see if that improves their experience.

Yeah so much for it being a Maint day problem happened again this morning had to log out then log back in using desktop not the Battle net app.