Just to throw a klinker in here...it's not bread pudding per se, but as an aficionado of bread puddings...I simply must recommend the Sticky Toffee Pudding at Rose and Crown. Mmm-mmm-MMMM!
If I wanted strict "bread pudding" I would have to say Ohana's, but I have not yet tasted Raglan Road's.
The best bread pudding of my life (thus far) was served to me in Willaimsburg, Virginia at the King's Arms tavern on Dog Street (Duke of Gloucester).