I was watching a Minecraft video, and during it they made Mushroom Stew because they were running low on food. The thought occurred "You should have saved them and grown more." Of course, then the thought hit me: Mushrooms use Bonemeal to grow into Giant Mushrooms. Were they also nerfed? I went into Snapshot 13w04a and tested.
Of course, they still grow instantly with a single use of Bonemeal. This seems inconsistent to the rest of the changes. Considering how they grow, it would be more consistent to require two uses.