I have a two-person service team. It would be great if I could assign an action (prepare acct opening docs) to both members of the team, so that both members can see the action, one can complete it and then it drops from both of their to-do lists. One way to do this would be to create the ability to have distribution list of  multiple users. I would create one called Service Team that I could assign an action to (in this case the 2-person service team).  Both can see, edit and complete the action and the first that would would mark it complete.