Not sure, but I will let you know.
That said, I was toying with the map editor and RL has provided example tracks for most of the skill games and track concepts + they have hill climber and loose nut examples from the first Trials as well as a 4 way mini-game. Between all the tutorial videos, the approachable editor, and examples there should be stuff turning up sooner than later.
That said I think the best stuff really will be gameplay content that is inline with the core game. New mini-game types will be where it is at IMO. The core of Trials is so good the non-core minigames imo feel much flatter. Cool concepts and all but the bike physics and dynamics are so good it makes everything pale in comparison.
But so he could finish the first bunch of tracks in Trials HD no problem, but can't finish any of the new ones now almost a year later. The old ones had only one or two obvious spots where he had trouble, really. And yes, all that on the beginner bike - I played the beginning of the game with him. But anyway, like I said, no biggy - it was just that I was basically looking forward to this as a father-son activity so to speak. 
