Well that's bittersweet for me. I hate seeing Kamui go but I'm really excited at their new line up, it's going to be great watching Sauber yet again. I've always liked Hulkenberg a lot, and he showed some great resolve in the USGP so I expect him to podium a couple times at least. Esteban, I'm not sure, but as long as he fairly finishes ahead of Nico a couple times then I think we can call their pick a success. Getting into Q3 would also merit.
As for where Kamui could go, I'd think he's still worthy of F1 for sure, I'd actually love seeing him at Williams myself, but Bottas is most probably getting that seat. I wouldn't hate seeing him at Caterham, but that would kind of be a waste in my book, but they're on the hunt for more money which is why they seem to be dropping Heikki so that's not gonna happen for Kamui. I don't know what Marussia's up to, but the rumors are rife with Chilton getting the seat for some reason. I don't think that'd be a good experience for him anyway.
So he may pull a year as a test/reserve, then hopefully something opens up in 2014 and he can get back in the game before it's too late. But he'll need to bring money, so it'll be an annoying year for him business-wise.
So other than all that, the hottest seat is indeed Force India. It's really hard to tell if they'll be able to move up next year in performance, but a lot of their potential would probably lie in who they pick to drive. That being considered, I think Di Resta needs to take a #2 spot. Although I'd love to see Jaime there, I don't think they'd go for it. (btw I think he's on Caterham more likely) They want someone with more experience, Nico was the perfect team mate for Di Resta, so someone like him with a bit more experience would be ideal I'd say. And that man would be Kamui. I think he'd be a great fit for them. Someone that knows their ****, brings home the car, can put in consistent results, qualifies really well, a great great benchmark for Di Resta to try and beat. But teams always need money and he can't really provide that so if they do take him on it'll be at a risk. The only other thing I can think of for them is them opting for a brand new driver, but one that just happens to have a huge backing from somewhere - so we may see some new random guy pop up out of nowhere. I think the talk of all the retired drivers charging for the seat (Sutil included) is just fluff to be honest. FI won't be desperate for experience that much, which is why a mix of talent and experience that Kamui can bring seems more attractive to me. Rubens can probably put in good results, but we can count on them not being great, so why go with him? He doesn't have the money either. Just because he approaches the team doesn't mean he's waiting by the phone for them, it only makes sense, if you're a driver and have the qualifications, you'd be stupid not to at least send your business card to the office. Truth is we don't know to what capacity guys like Rubens and Jacques have submitted their interest to the team, could be anything from an E-mail to a handshake, with the fore being more likely.
Can't wait for all the confirmations.