Three or four years ago I remember getting bumped from AA96 ORD-MXP on the Saturday nine days before Memorial Day. They gave me a hotel room and meals vouchers and put me on the following day's AA96. That ended up being oversold too. So I volunteered again, and AA flew me the same evening to LHR, then on to LIN on BA. I arrived about 30 hrs later than planned, but I managed to visit the Art Instiute in Chicago (love it!) and gain $1350 in DV vouchers.

Of course, it's always a matter of luck. I've flown ORD-MXP many times on weekends in May, and that's the only time I was bumped.