The IAC is what I'm waiting for.
Trying to put my SpaceX fanboyism aside I think PR wise BO opted to announce this now because the BFR & Mars architecture is going to be a larger and much more ambitious rocket program..and size is all that matters in unflown and yet-to-be-built rocket designs. I think both large designs are likely to succeed, and it's the only way true rapid re-usability can succeed. Due to how the rocket equation works, a significant percentage of your rocket will always have to be fuel. The only way to get around this is to massively scale up your rocket in size, so that you can devote a greater absolute weight towards reusability systems.
An example: A typical mass fraction of a rocket is around 90-95%, meaning 90-95% of the rocket by mass is fuel, and 5-10% of the rocket is everything else(structure, tankage, engines, payload, etc). This will always be the case because that's how the math works out. However, if you scale up the overall mass of your rocket, your 5-10% actually becomes meaningful amounts of mass that can be used beyond the bare minimum of mass necessary for tankage, structure, engines, etc since there is a baseline amount of mass that those will have.
Edit, I recently finished my sim and corresponding write up..it's not too math heavy and has pretty graphs. I want to post it here...I'm always looking for feedback. Any ideas on how to upload a pdf here?
Double edit: It doesn't really come through too well, but I do want to say this is very exciting and any competition will only be a good thing for the future of space travel. This is where it all starts.