Looking at the datasheet graph, I see that is indeed the case (although 12 Mhz might be an option).
Yeah, this same topic has come up half a dozen times in the past week or so. If you interpolate
the datasheet carefully, you'll see the 3.3V point corresponds to 13.3 Mhz, so a little closer to
16 Mhz. However, a lot of guys still say this isn't 16 Mhz.