I think they're making a big mistake using the word "maintenance" for this downtime. It makes it seem like it was expected and planned for, and I think that's why so many people are pissed about the lack of an ETA. They should be calling it "an emergency repair," which would set the right tone and give people the right expectations.
And their announcements are just as bad. They keep promising to give information and updates, but then the next update just says "We'll give you more information and updates soon."
They should have done something along these lines.
First this:
"During this early release period, we have encountered an unexpected error which resulted in our bringing the server down immediately. While we are working as quickly as possible to restore service, right now we can't predict how long that will take. We will update you with more information as soon as possible."
Then, an hour later:
"We apologize for this extended downtime. The problem has turned out to be difficult to track down, and while we still can't predict when this will be solved and hope to have the server up any moment, it's now looking like it will be a longer process that might last several more hours. Please check back often, but in the interest of not wasting your time, we want to inform you that this looks like it might take a while."
Then, some time later:
"We apologize again for this extremely long downtime. We are doing everything that we possibly can to fix this, but obviously it's not happening as fast as we'd like. We won't be issuing any more updates, because the only news we can give at this point would be to repeat that we are working feverishly on this. Our next update will be when we happily inform you that the server is back up."
Notice that I do not thank you for your patience anywhere in there, because nothing is more offensive than being thanked for your patience by someone who is pissing you off and making you feel impatient.
If they did that, the players would be in the loop, but they still wouldn't have had to promise anything, or explain anything that they don't want to get into.