The F-35B isn't going to be cancelled, there is too many countries depending on it and its capabilities make it irreplaceable (in the next 20 years).
The A and C can be dropped, as long as the US wants to continue to use 1960 designs for the next 20 years.
Peter - the F-35B
could be cancelled and that is what is being loosely thrown about here as a mere supposition. I'm sorry but if the F-35A goes the Programme goes as the cost per JSF will become unaffordable; also FYI there are more countries interested in buying the A than all of those buying the other variants - USAF, Netherlands, Turkey, Australia, Denmark, Italy, Singapore, Israel, Japan. The potential order book for the A is around 70% of the total anticipated JSF build. Performance in test will dictate how that changes and right now F-35B is due to IOC 2 years later than the USMC desired therefore 'nearly ready' is a tad optimistic. I think nearly ready technically occurs in Nov 2014.