Pretty-straightforward. I actually have an i5, and when it's overclocked to above 160 FSB CPU-Z will sometimes claim I have an i7 and display the i7 icon, however under description it still lists me an having an i5. I'm guessing the OC is just tricking it, but is it anything to worry about? No I'm assuming?
CPU-Z is not 100% accurate. But it does get updated often enough so maybe the next version will identify it correctly.