Today I've seen two stories about Caterham's second seat: the first, on a Spanish site reckons that Jaime Alguersuari has it, whilst the second, a Finnish site is saying that Petrov will retain the seat for next year , primarily based on the fact that Bernie wants a Russian upriver on the grid for 2014 and the new Russian GP.
Seems a bit ridiculous but always possible, you just never know with Bernie.
The seat is also being chased by Bruno Senna amongst others and I am of the opinion that it will go to the highest bidder, as long as they have a modicum of ability.