How come some of the pictures I've seen of the Prius' dashboards have their power button labeled "Engine Start Stop", while mine says "Power" along with the universal power logo (the O looking thing with the vertical line through the top)? Am I special?
No, you have the final version of the button. In pre-production models the button had a different label. I like the POWER one best. Notice that the O with the vertical line is the (almost) universal sign for things with a power on/off button or switch.
The reason they changed it was because people thought that they can turn the ICE on and off that way, during the drive.