Check out MythForums to get the following straight:
In recognition of the fact that some people belong to one order when playing TFL and a separate one when playing Myth2, we now allow you to join one for each !
When you go to join an Order/Clan, just select which game you're joining that order for.
All existing members that are registered in an order have defaulted to having theirs be a Myth2 Order to keep things simple. If you want to change it, just go and join it as a TFL order, then leave it as a Myth2 Order. Confused ? Check it out and it should make sense to ya =)