One or two movies are not the be all and end all of people's exposure or experience of an event like 911. I suspect that the movie is going to freshen the memories of how they dealt witrh that for a lot of people. It was only five years ago.

Exactly. In fact, because it's still fresh in people's minds, I'd hope they're more likely to question whether what they're watching is accurate or not, because they can compare it with their own memories about the events in question.