So - Wrath is on the way. Progression is slowing down, guilds are having a hard time recruiting (or just keeping raiders, in some cases) - what's a GM to do about morale?
How about "game within a game?" It's worked for so many pre-school teachers, right?
~~ Bring in the Clowns: Have your guild tailor make up some crazy outfits. The Haliscan Pantaloons and jacket, for instance. Or perhaps Green Winter Clothes. Set a time for everyone to log in on their alts and pass them out. Once everyone is dressed up - go raid Ironforge!
~~ Wowpperware Party: (to outfit lowbies) Pass out Hot Cider and Delicious Chocolate Cake. Have your guild crafters take orders for gear from guildies - make sure to offer with- and without-mats prices. ("With" should probably be free, these ARE your guildies, after all.)
~~ Broke as a Joke: Invade a new server. Challenge your guildies to achieve certain goals within so many days of play; i.e. the most money, the highest crafting level, a flight path at the furthest point from his / her starting zone, etc.
~~ Big Brothers / Big Sisters of Azeroth: Have each player adopt a lowbie for a day. Instance runs, help with group quests, providing mats for his / her crafting profession, etc. Load up on some ale and take your lowbie fishing for the evening.
Silly? Cheesy? Of course - that's why it's fun!