I have a different theory...
First off, with the Sniper and Spy update, I developed a theory about what Valve were doing. Instead of releasing an update and having everyone swarm the class, they released 2 class updates which directly compete with each other. So you had Snipers being taken out by Spys, Spys in the hidden places and Snipers in the open, and a general equilibrium between the 2, so other classes could actually enjoy themselves. Because of this, I think the next class update would be Engineer/Demoman. It would prevent the millions of turrets, and give the many Demomen something to keep them occupied. As for this update, well I expect a new game mode. Something that involves friendship between both sides, and fighting the administrator. That would explain why there's all those sound files in the game itself.
First off, with the Sniper and Spy update, I developed a theory about what Valve were doing. Instead of releasing an update and having everyone swarm the class, they released 2 class updates which directly compete with each other. So you had Snipers being taken out by Spys, Spys in the hidden places and Snipers in the open, and a general equilibrium between the 2, so other classes could actually enjoy themselves. Because of this, I think the next class update would be Engineer/Demoman. It would prevent the millions of turrets, and give the many Demomen something to keep them occupied. As for this update, well I expect a new game mode. Something that involves friendship between both sides, and fighting the administrator. That would explain why there's all those sound files in the game itself.