Auction House Unavailable

I see no posts discussing this and no notifications in-game about the auction house being down, so making a post.

The auction house button has been greyed out and disabled (the tooltip states "The Auction House is currently unavailable") for me for the last 30 minutes or so.

Restarting the client or changing heroes does not change this at all.

Is it currently down for maintenance, and I just missed a notification somewhere?

Same here, they are probably doing some changes. It's been extremely slow today.