I bet 99% of Torontonians (and Southern Ontario'ans) don't say 'aboot'. However... North Western Ontario... anywhere west of ThunderBay... they definitely DO say 'aboot'.
Discovered this on a roadtrip across Ontario a couple years ago... I was shocked. Of course, this is also a tourist area (hunting/lodges) for Americans... saw a ton of US plates... so now you know where the stereotype comes from.