As a former guild leader in World of Warcraft I can state that yes indeed it takes a certain level of finesse to get a group of 40 volunteers (out of 100+ members) motivated to accomplish an already pre established goal defined by Blizzard. The game has incentives already built into it and the formation of a guild is relatively easy process. WoW is truly gamification at its finest which is used as the primary motivator.
It was a lot of fun. But it was a huge time sink. So much so that to say it was distracting would not accurately describe it.
Word of warning: if you don't play it, don't start. Time is a valuable commodity which you can't earn back once it is spent. There are other ways to learn leadership/soft skills that are more productive.