We rediscovered last night that when you do a quest turn-in, everyone in the group gets XP. I don't think this is split among everyone in the group, but I assume each person is given an equal amount of XP. I suggest someone test it out.
Anyhow, if this is the case, I recommend that we all hold on to those quest items until a bunch of others on online. Then try to get a full group together and go turn in the quest items at the same time.