If someone ever comes up with a practical method of creating reliable software then everyone would use it. You can always find a programmer who will claim that they would of done it better... For all we know whatever Toyota is doing is way better than what everyone else is doing and this is their only safety critical bug (assuming that the bug actually exists)...
In the end the software is either correct or it is not.
The information that has been released so far, especially Michael Barr's comments on it, suggest that this is far from the only bug.
For example, http://www.edn.com/design/automotive/4423428/Toyota-s-killer... quotes Barr's claims:
"Toyota’s electronic throttle control system (ETCS) source code is of unreasonable quality."
"Toyota’s source code is defective and contains bugs, including bugs that can cause unintended acceleration (UA)."
I am a little appalled at the number of apologist comments on this story. There is mounting evidence that this wasn't a "it could happen to anyone" bug, but rather a serious violation of software engineering ethics. Code must not kill.
Some of us do not believe that such a thing exists in any meaningful form. In the past every approach to creating reliable software has failed to deliver. That makes it hard to believe that any particular approach is finally the answer.
I agree that the Toyota software is poorly written. That in no way means that conforming to a particular standard or method would of automatically produced software that was more reliable.
In the end the software is either correct or it is not.