Hi Will
It depends a bit on how smooth the game engine development goes.
Currently the frameset is under way. The engine is being designed directly towards being open for modifications to the game.
One of the areas where we are still lacking people is the graphics department, so our hope is that with a very basic alpha release we might encourage more people to start creating in-game material.
So I wouldn't dare to venture a guess at the moment untill we know how well the scripting implementation works out (the plan is to implement PHP as the scripting language since its something a lot of people are familiar with). Once that is in place, the floodgates should open and development speed should accelerate (since even slow-coaches like myself will be able to contribute more ).