Ariane 6 looks like it will be a fine rocket. Should be quite competitive if they can get it to market before, say, 2010, and if SpaceX's reusability efforts come to naught.
Otherwise, I fear it'll be much too little, much t0o late.
Well, but SpaceX hasn't. They have not reused any rockets. They've landed a few rockets, they've test-fired one of the landed rockets. But that's far from a track record of reliably recovering their rockets, turning them around and sending them back up that could drive the massive cost benefits that they hope for.
I'm not really playing skeptic here -- SpaceX's progress has been incredible, and I'm inclined to believe them that they can do it -- but it hasn't happened yet.
Otherwise, I fear it'll be much too little, much t0o late.