New in Wolfram Mathematica 7: Current & Historical Weather Data  previous | next 
List Current Temperatures in World Cities
The current temperature in Celsius for the 6 largest cities.
In[1]:=

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Text[Grid[{CityData[#, "Name"],  

     Row[{Round@WeatherData[#, "Temperature"], "\[Degree]C"}]} & /@ 

   Take[CityData[], 6], Frame -> All]]
Out[1]=