You might want to ask Judith Miller about how carefully the NYT protects its valuable reputation...
In this case, though, I'm not saying that the NYT is subject to the same incentive structure as a blogger; but that the writer is.
The Times obviously wants to avoid being embarrassed by its writers; but it also has no incentive to retain writers who are unproductive or uninteresting. This means that the writer(just like the blogger), is subject to a continual pressure to produce content, and content that gets read. If they don't, it's not as though there is a major shortage of aspiring writers...
Without access to the vehicle logs, there isn't anything obviously fishy about the story so no obvious reason(or ability, without going straight to the company they are writing about, which presents obvious problems) for the Times to become suspicious before running the story. If, in the end, it becomes clear that the writer was 'improving' upon the facts, I'd expect the Times to terminate him; but we haven't reached the point where we get to learn whether or not that happens yet.