I've just returned from the US 3 days ago.
The guy at Dulles was just businesslike with a gruff edge, which is fine by me. But coming back, the guy at Amarillo was, i think, either flirting with me or just being overly nice... telling me that I look SO much better in person than I do on my passport photo, big smile, lots of eye contact. It kind of grossed me out, either way.