Considering that Photoshop is one of the most popular pieces of software in the world, its obviously going to win the poll!
But ofcourse, most people don't need many of the features of Photoshop, they could do everything they want with much simpler programs, but since Photoshop has such a strong customer base and is used by basically everyone in the printing and graphical design related industries for years now (since it is very well written software), its obvious that Photoshop is going to continue being the most popular for quite sometime. It's even become a slang word that a lot of people use these days, saying that they will "photoshop" something, meaning they will modify a photo on the computer! How often do non-computer geeks say "i look fat in my photo so i'll just Gimp it later!"
But considering how expensive Photoshop is, I hope that more people use other freeware alternatives since Photoshop is way more than what most people need. Apparently there are more people using cracked versions of Photoshop than any other piece of software in the world!
Cheers,
Shervin.