According to the French programme AUTOMOTO, Marussia has been turned down by Renault for engine supply in 2014. With Cosworth leaving F1 at ther end of this season, Marussia is looking for an engine for next season. It will be Mercedes or Ferrari. Toro Rosso plans to switch from Ferrari power to Renault next season, opening a door for Marussia to take over and receive a Ferrari engine from 2014. Taking on Ferrari Academy driver Jules Bianchi at the 11th hour now makes sense.
That nobody but Marussia wants to buy Ferrari engines is worrying (I´ve read a rumour about Sauber switching to Mercedes-Benz).