I cannot get too interested in the conspiracy theorists asking whether the US government doesn't now, due to its ownership of GM, have a conflict of interest when it starts publicly raking Toyota over the coals.
Item One: Toyota didn't handle this particularly well, and there's at least some suggestion that they downplayed problems that were killing people.
Item Two: Many people in our government already had ample bad incentive to rake Toyota over the coals, because they come from states where the UAW is popular.
Now, there's no question that this is good for American automakers, since their lingering reputation for terrible quality has historically handicapped them in competing against the Japanese. But I'm willing to bet the biggest beneficiary is Ford, not GM or Chrysler. Ford is perceived as basically healthy; the other two, as crippled and weak.
What it means for Toyota should be a management shakeup. The US is a huge market, and they just did brutal damage to their brand on one of their two or three biggest selling points. People are going to want to see rapid commitment to making sure this never, ever happens again. Moreover, it would be good for Toyota to actually make such a commitment. How do you design floor mats that will kill people if used improperly? Giving engineers power is a great way to get quality improvements. But they have to keep in mind that they're designing cars for normal people, not engineers.