I don't know but if they are randomly generated (as we know), it makes sense.
Yes. It was officially stated that you will be able to play your own tracks online with your friends
I wonder if there will be one custom track thats 'most popular' that everyone plays on...
If so, who will be the one that makes it. I can't wait for a guy named FunnyLumpkins to be the creator of the most played track. lol