OK, technically, I am on the Blizzard mailing list, so not spam as such, but an advert.
An advert for something I am already paying for and they know it.
An advert for something that doesn't fucking work yet.
Really Blizzard, why rub salt in to the wound? Why?
P.S. the most obvious problem is the garrison instance. As I understand it that is a single player instance, it is your garrison/fort/town. So why the hell is that not run on the client and not an instance server which clearly cannot cope?!