Canadians say 'about,' but they pronounce the 'ou' like the 'oa' in boat. Hence, 'aboat.' The Canadians I know (Who are technically French-Canadians) say 'aboat.' When you think about it, they pronounce it more eloquently than we do.
My Friend: Er, "Canadians don't say 'aboot', they say 'aboat.'"