This is the same as saying, "Your web site has a slew of bugs in the JavaScript for signing up for the newsletter and the CSS is terrible and that's why it doesn't validate credit cards properly. They never point out the actual code that causes the acceleration problem - they just malign the code in general. Looks like a lot of lawyering by people who want to squeeze more money out of Toyota.
Toyota claimed the 2005 Camry's main CPU had error detecting and correcting (EDAC) RAM. It didn't.
Unintentional RTOS task shutdown was heavily investigated as a potential source of the UA. As single bits in memory control each task, corruption due to HW or SW faults will suspend needed tasks or start unwanted ones. Vehicle tests confirmed that one particular dead task would result in loss of throttle control, and that the driver might have to fully remove their foot from the brake during an unintended acceleration event before being able to end the unwanted acceleration.
In other words, they used non-error-correcting memory, and the investigation found a code path that would lead to the observed behaviour if a single bit flips.
>> ...driver might have to fully remove their foot from the brake during an unintended acceleration event before being able to end the unwanted acceleration. <<
"Might" is a weasel word you use when you don't have proof. Are they saying that the the system is non-deterministic? Seriously, you can say it "might" cause the problem, or you can run tests that cause the problem. Even if it is non-deterministic, you could run 1 gazillion test and get a percentage. Then you could figure out, based on the amount those system get used, how often you'd expect acceleration to be uncontrolled.
And it still doesn't explain why it mostly happens to the elderly.
Some of the issues identified in this review could have led directly to unintended behavior (e.g, lack of ECC memory, and coding practices that could lead to stack overruns).
Besides, why would bugs cause more problems when the driver is elderly (http://www.forbes.com/2010/03/26/toyota-acceleration-elderly...)?