Simpleweather did one odd thing: when I typed my city in the search box, it showed one result. Since it didn't have a line beath it I didn't even realize it was a hyperlink.
If there's one result, take them to it.
One good thing tho: it knew that that Celsius is used everywhere outside the US.
I've always been a fan of wunderground (http://wund.com). In addition to the main site, it has similar functionality to what's described in the article with its mobile/iphone subsites.