Hidden Power

So as many people have pointed out, the typing of hidden power seems to have changed after gen 4 started being released. However, I was just searching through all my Pokemon with ice type moves and found my Porygon 2, which used to have ice type hidden power and now has (or appears to have) water type hidden power. So is it possible the apparent change in type is just visual, and all the types are actually still the same as before? Has anyone tested this by taking hidden power into a gym and checking effectiveness?