WoW launcher and downloader causing validation errors [Updated]

I and many tipsters have encountered some issues tonight when trying to launch the game.

Here's what we know:

The Launcher is downloading something small.
It is taking much longer than the 2 minutes estimated.
Sometimes the download fails.
Once the "something" has been downloaded, some are getting "unable to validate game version".
Constant attempts to log in appear to make the error go away.
There is no indication of what has been downloaded.

Here's what we don't know: What was downloaded.

We will update you as soon as we know anything.

Please note: There is no indication patch 3.3 is dropping. NONE.

Update 8:55pm: Blizzard says that the downloading issues are due to "prime time" and gives some advice in this link, mostly suggesting to wait.

Update 8:44pm: Blizzard is calling this a "Tools Patch" and saying that "Safe Mode with Networking" is solving some people's problems. Obviously the issues are not fixed.

Update 8:30pm: Blizzard says they have fixed the issues. Anyone still having problems should take the steps outlined in this link.

Tags: breaking, download, downloader, invalid, invalid-game-version, patch, unable-to-validate-game-version, validate, version