I've had the same experience with TripIt Pro (aren't we supposed to abbreviate everything here? Shapp we call it TIP? ;-)

What often happens, though, is that TripIt Pro reports a delay as soon as they know about it. Then they report the next delay for that flight. Then the next. Then... they report a "PullBack", where the airline has somehow partially undelayed the flight and now the ETD is earlier. This results in several notifications per flight and perhaps AA avoids notifing delays when they believe they'll be able to reverse it.