Not that I want oyou to feel any worse but if I remember correctly there can only be another 2 Doctors before the series is buggered..
I KNOW! I think that is what has me most cross about the whole thing. They are running through regenerations like there is an infinite amount of them!
I have a sneaky feeling that they've already set the groundwork to solve that though, Donna. And no I don't mean the physio although that could lead to an interesting series...
"We have to stop this CyberDalek death ray from destriying the earth. Quickly Nick, plug this microwave emitter into the power supply over there, now insert this teatowel...."