I can't wait to see how it copes with British accents. Not just English vs Scottish etc - but the hundreds of variations.
I grew up in the East Midlands and now live in Leeds, 70 miles north. The difference in accents is night and day (although no-one in the UK knows what a Nottingham accent is). There's even a significant difference between a Leeds accent and the next city, Bradford (about 5 miles away).
I really hope Siri has some sort of unobtrusive training built in...
http://www.guardian.co.uk/technology/2011/oct/12/iphone-4s-s...