I know for a fact there will be no Fiesta ST/XR4 turbo because :-
1. The current model Fiesta is the last generation Fiesta before Ford discontinues it.
2. With pre-jurassic motoring mentality people have atm, FPV won't engineer a Fiesta XR4 Turbo.
EDIT :- but yes, as Photn said... the next generation Ford supermini will use this 1.6l Duratec Turbo as shown here..