Weather Widget - How to fix it
John Gruber just posted a short set of instructions on how to fix the weather widget if it shows the wrong info for your city. Apparently, the weather widget just picks one city rather arbitrarily from its list that has the same name as whatever name you enter. So, when I entered Heidelberg, I got Heidelberg, KY, and thus it showed impossible temperatures and pretty much the opposite daytime/nighttime cycle. Anyway, the fix John found is simple:
After you enter the city name, hit return, tab, or enter. That will show you which city you got, and also bring up a menu with all other available cities of the same name. That this should be more obvious, is of course something that I hope Apple will address. For now, I'll go file a bug.