Thanks for the warm welcome! Unfortunately, I don't know how many teams there were in total. I think there were four (maybe five) teams there while we were checking in, but to be honest, I'm not really sure. Our flight ended up getting delayed four hours, so I had some time to explore. While I was roaming the terminal in search of food, I came across another team just coming through security at around 9:30-10:00 (although to be honest, this is a rough estimate). I didn't recognize that team from before (nor the team being interviewed at the gate), so that makes the total six or seven teams that I saw. Don't quote me on that, though, as I was running on less than an hour of sleep and distracted by my excitement at traveling with the Amazing Race - something I've actually always wanted to happen since elementary school.
Also, it turns out the blonde woman with pink tips is from the same town (Morristown, NJ) as I am! The team with the guys in blue were from Oklahoma, and I recall there was another from Chicago. For what it's worth, I don't think there were any from California; my friend is California, and I remember her expressing disappointment that none of them shared her home state.