Anarchemitis said:
What would a Team Fortress 3 bring to the table that couldn't be applied by another update to TF2?
Updates just refine the game, not change its nature. TF2 is a shallow, dead easy to pick up, visually attractive class-based FPS that works as a good selling point for Orange Box. There's no point in trying to fundamentally change it from those premises, just keep new items coming in now and then to keep the game fresh.
TF3 could go for any number of things, but the most obvious would be to make it fast, intense and deep like all the pre-TF2 games, and include a ton of elements to help players get better and to really function as a team (something that virtually never seems to happen on TF2 public servers). Detailed tutorials that range from easy to extremely challenging (see Quake Live, Virtua Fighter 4 Evolution), visual elements that assist in teamplay by showing things that good teammates would otherwise have called out to you (see Fortress Forever), maybe a personal ladder rank, matchmaking and lobbies for "pick-up teams". The players would have the tools to easily form a team out of willing random people at a given ranking range for the purpose of playing one game, without belonging to a clan. The market focus would be from semi-casuals to tournament players instead of TF2's casual to average.