I got in on AA47 yesterday and it was a mess at ORD immigration. Longest queue I have ever had to wait in and the line at one point was stretching a couple of hundred feet all the way down the corridor towards gate M1 in addition to being completley full in the ropes for the US Citizens line. The flight was early, getting in by about 430-440 but I wasn't on the tram until 530-535. Luckily the DHS agents opened up some other stations otehrwise I would have definitely bewen waiting a lot longer. Teh problem was taht a few AA flights, a LOT flight, and a few others (LH maybe?) all got in at around the same time.