With all these API's I wonder about conflicts of licensing and terms. They all have their little niggles: no realtime, no commercial use, limited number of queries, limited by directory, etc. etc. I have a feeling people are going to break lots of these terms without realizing it. Of course, the data originators probably won't mind until either their servers start getting crushed, someone tries to sue them for bad data, or the masher makes serious bank.
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