not to good of an idea the groups and shareable loot seems like a good idea in theory(but in theory aquiles never reaches the turtle(olc calculus problem))
my point you may ask is this the reality is I rarely see more that 40 people on the server and even so never seen over 100 players online so even in a full server like the oficial wow it can take anyware from 1 min to over 30 waithing in queve to do a dungeon i dont want to imagine the time get together a ful group foe this purpose...