I called the Chicago Rabbinic Council and asked one of the main rabbis in charge whether it was kosher - well, actually I left a voice mail message. Just now, he called me back and after apologizing for taking so long, said that he had done the necessary research and that the result is that Pepsi Natural is both Kosher and Parve.
Just so that this information can be properly propagated on search engines, if you are wondering, "Is Pepsi Natural Kosher?" the answer is a resounding yes.
