Lots of GameCube and XBox owners own a PS2, most such people are likely to have bought a 360 or Wii by now considering these platforms already received sequels to the bulk of their popular XBox/GameCube franchises and relatively low entry pricing, also someone with PS2 backwards compatibility may not see the need of owning a PS2.
The 360 is most popular in the states where its install base is larger than for the rest of the world. For the PS3 just the European install base is already bigger than its US install base despite the delay of introduction.







