That's not even remotely the same. The server sent a hotfix patch out at 1 before midnight, which activated MoP content.
For services it's a bit difference, they need to enable it both on the website, wow and the wowshop, which requires a small maintenance.
And if they are putting up WoD preorders with it, you can be sure they'll use a maintenance for it, so there's not many issues with it.