There is no "norm" but metamours that get along and are not only friendly but considerate to one another ... everyone considering each other and giving as much as is comfortable, seems to work better.
Once that is established there is any way it could go from there... its all negotiable with honest communication and creating fluid boundaries as you go... boundary negotiation in my life is a daily occurrence, and more often than that sometimes... at least daily. Sometimes we want to all hang out and sometimes, we don't. We are not new to this though and at the beginning we had to be very honest about not wanting to spend time all together sometimes... it was a learning curve and got easier with time.
I would suggest looking at threads with the tags "triad" "vee" "secondary" and "metamours" ... or whatever you feel you are interested in of course... LR had a good point about the blogs section also.
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