I sure do hope that the new dreamland is the only place you will find giant mushrooms naturally.
Also, I just finished this new minecart station system. I don't feel like going through the trouble of taking pictures or making a video, if you guys want to check it out here is the save:
http://www.mediafire.com/?i4f9d85c9lmu4fk
I've worked on designing it so that when actually applied to the game in a building or whatever you will only see mine tracks, none of the circuitry, assuming you build it into the building right.