Caterham are in administration and Marussia are strapped for cash so neither of them will be in the USA or Brazil and probably not in Abu Dhabi.
There is too much of a gap between what the rich teams get paid in prize and attendance money and what the tail-enders pick up. This funding makes it near on impossible for a new team to break through unless they come with huge backing from, probably, a main motor manufacturer, and even then nothing is sure..... look at Toyota, Honda and BMW.
If F1 is not careful it will go the way of MOTO GP with a few "works" teams in with a chance of winning and dedicated privateers, who do it for the love of racing, making up the rest of the field. I wonder if that is why Bernie was suggesting that main teams run three cars........ It could end up like the 60s, 70s and 80s when there were loads of teams, some with only one car, trying to make it onto the grid via pre-qualifying.