Prince.M5
Gutierrez is more of a realistic choice but recently Monisha Kaltenborn made a comment that she's a bit uninspired by Gutierrez's performance in India means that he might be on hold. But if anything, he remains the favourite.
Gutierrez was very unimpressive, he was slower than Van Der Garde in the Caterham, a car which is 2-3 seconds slower than the Sauber. His GP2 season was also fairly unimpressive, he really should have been challenging for the title.
My picks for the remaining seats are:
Lotus: Grosjean. Despite all the first lap accidents, he has shown impressive pace, and surely has e potential to be a race winner, or maybe even more.
Sauber: Gutierrez. Despite the reasons above, Gutierrez gets the seat over the highly impressive Robin Frijns because he bring s more sponsorship money, crucial to a midfield team like Sauber. Look for him to be on a short leash though, a poor season could see him lose his seat for 2014.
Force India: Sutil/Alguesuari/Buemi/Bianchi. This is a tricky one, will force India continue the pattern of promoting their test driver, or will they go for a known quantity in Sutil? Or do they go for an ex Toro Rosso driver, both appear to be on the market.
Williams: Maldonado and Bottas. Despite not confirming either driver, the general consensus is that this is the lineup Williams will have next year, and I see no reason to disagree. Maldonado is clearly fast, and is getting better at finishing the races. Williams believe they have a future star in Bottas, and are eager to give him a shot to show what he's got.
Caterham: Pic and Kovalainen/Petrov/Alguesuari/ Van Der Garde. Pic has impressed in his rookie campaign, and seems headed for Caterham next year. Who will join him is another question, with plenty of drivers willing and able to fill the other seat.
Marussia: Chilton. Marussia will continue its trend of giving Glock a new teammate every year by promoting Chilton to a race drive. Max has been fairly impressive in GP2, and brings plenty of money, so this seems like a decent choice, although why they let go of Pic is puzzling.
HRT: Clos. With Ma Quing Ha not yet ready for F1, HRT promote their other reserve driver, Clos, to a race drive. They also achieve their goal of having an all Spanish lineup, so this move makes sense.
Of course this is just my view, please don't take it as fact. Sorry for any spelling/grammar errors, I typed this whole thing on my iPad.