I don’t think we’re going to see interest in a thirteenth team until such time as Caterham – and possibly one of the other teams – starts scoring points on a semi-regular basis.
Personally I would love to see Prodrive get the 13th slot because then we, potentially, could have Aston Martin in F1, which would be awesome.
Prodrive isn’t going to happen any time soon. They tried to enter in 2008, but that entry hinged on customer cars being allowed to enter, and some of the established teams – namely Williams, I believe – didn’t like that. Plus, they’ve had a few other abject failures elsewhere: the AMR-One Le Mans car was an absolute embarrassment, little more than a submarine on wheels. Likewise, they handled their Mini WRC entry so poorly that BMW pulled all their funding.