What in my mind demonstrates Captain Sullenberger's professionalism aside from his flying of the aircraft is that he knew, from studying and knowing his aircraft, that the correct ditching attitude was 11 degrees. A very small note in the QRH states this. Any more than that and the aircraft would have slammed down on the water, any less and the engines would have "bit" into the water and caused a break-up.
For those who start waffling on about Alpha floor look at Fatflyers post.