Every once in a while I'll be perusing the archives of my site and I'll stumble upon a typo. I'm always a little upset with myself when I do, but typos happen, especially when you're writing entries like this on the fly with little time to proof.
There are typos and there are typos. An official tribute sign erected on the fence surrounding Ground Zero actually misstated the date of the 9/11 terror attacks. The sign, which memorialized victims killed in the Pentagon attack, noted that "September 11, 2002" was a pivotal day for the country and the world. You can see for yourself here.
How is it possible they could get the date of 9/11 wrong on a memorial of this nature? Before the characters were carved you'd think it would have been proof read a couple of dozen times by more than a few pairs of eyes. Typos happen, but unlike my site The Port Authority can't edit a little source code and hope nobody noticed.