I just bought a pair of Nike Air Zoom Infinity Tour (bit of a mouthful), and a lot of the reviews suggested you needed to order half a size larger than usual. However I just ordered my usual Nike size 9 and they fit fine. I don't think they would suddenly change their sizing, unless they are making different sizes for different markets.
Is it possible that Nike make a slightly different shape in different regions? For example maybe research has shown that American men have wider feet than Japanese men. I've always noticed with clothing that American golf shirts tend to be more baggy around the midriff. I remember struggling with a Durex product in Asia which was much smaller than the equivalent in the UK.