So...
My flight out of Charlotte left about 30 minutes late. The captain had made an announcement that they had not yet received clearance to leave the gate, but that we should be departing sometime soon. A few minutes later, two gentlemen were ask to leave the plane, but they would be put on the next flight...
The TSA was doing a random ID check at the gate, and, apparently, something didn't "look right" on the passenger manifest.
Needless to say, it was not the most pleasant way to start a flight.