That's bull. It should work well in every country it's sold in.
Not that it works great in the US either. I ask Siri for weather at my current location, she gives me the weather for St. Louis, Georgia even though I'm in St. Louis, Missouri. I can ask her specifically for weather in St. Louis, Missouri and I still get weather for St. Louis, Georgia. What makes that even worse is that there is no such city or town called St. Louis in Georgia. Google it, Wikipedia it, iOS 6 map it - there is no St. Louis in the state of Georgia. Siri is not just giving me weather for the wrong location, she's giving me weather for a nonexistent location. God only knows what virtual body orifice she's pulling the weather from.
And I've given up on asking her for the Cardinals score. Despite quantifying it with "St. Louis" and "Baseball" I still get scores for the Stanford Cardinals college football team. It's like the city of St. Louis doesn't even exist in Siri.
Not only is Apple Maps a joke in all corners of the world, Siri is quickly becoming a joke too. iOS 6 is a disaster. I really wish I hadn't upgraded.