Car & Driver magazine just did a very good test and analysis of the "Runaway Toyota" problem. In a nutshell, if the problem happens at low speed it is fairly easy to stop the car (the stopping distance increases slightly). However, at high speed, the brakes fade prior to stopping and the car does not stop. Interestingly, most drive-by-wire systems have a fail-safe that detects acceleration during braking and cuts fuel to the engine just enough to slow it down while leaving it running enough to keep power steering functional. That's what Toyota should do as well. A firmware patch.