This is a pretty tough question for me. I participated in some 40 man Molten Core raids and I must admit that they were pretty fun once I got the hang of what I was supposed to do. I agree that it really comes down to design. 40 man has its challenges as mentioned with the herding cats reference. I have also lead many 25 and smaller raids and managing the people alone tended to make it more enjoyable. For one thing, there is a LOT less time spent discussing loot after each kill. I do think that the smaller raid groups are more conducive to having a team that gels and really becomes a strong group. If you are trying to have a dedicated team, the smaller groups are also a lot easier as there are fewer schedules to try and manage. At the same time, the 40 man opens up the possibility to substitute more often and get to know more people. As Black Wolf mentioned, giant groups and lots of trash means a lot more time in a raid. This can be good and bad. I for one get extremely bored killing random trash that was added to the raid just to slow down progression. Lets face it, most trash does not present a difficulty issue. 40 mans can be great but they need more than the "kill these 30 pointless mobs to get to this boss" type of mentality. While the epic feel of a multiple night raid is a great feeling, it also presents more scheduling issues with more and more people. Being a successful 40 man raid leader is a true art and a test of patience. Either that or those who take it on are just plain crazy. If they do decide on 40 man content, it would be nice if there was some type of in-game management system to help with looting. Lots of the 40 man raids resorted to a DKP type system for assigning loot wins. It might be nice if there was a management tool available in game to assist with that. Maybe a way for the game to assign points based on participation of the members. With Carbine wanting a more social game, it is much more likely we would see large guild runs again rather than the random 25 man raid finder system. That means a much easier looting to manage via a points type system. If Carbine then provides a process for displaying the available loot in a raid, raiders could bid on the item ahead of time based on their available points. If the item drops on the run, the game automatically assigns the loot based on the bids. Just a thought. Ultimately, I have had more fun in the smaller raids with a great group of people than being part of a giant 40 man cluster.