One interesting thing to note is that the number of votes for 4 players is actually very small. 3rd Edition set the standard for the game to 4 players, and I always thought that must be the case.
I voted for 10 or more. I believe the game is certainly practical with that many players, provided you have enough space and the room isn't too loud. I normally would prefer a large group, certainly as a DM but also as a player. 6 or more players is generally what I'd say is ideal.