This isn't true.
The fact they have held the market is because they have good games on the system. The hardware obviously doesnt matter as much as people thought, since both gamecube and X-box have better hardware.
Some consoles might not be to peoples tastes, though its no reason to say they are rip offs...
EDIT: if this is true, graphics of the Playstation 3 are going to be superb!!!:
'Activision has already confirmed that Spider-Man 3 would ship on next-generation consoles, but at Sony's 2005 E3 press conference today, we got to see a real-time Spidey doing his thing.
The character was amazingly detailed, so detailed in fact that we suspected he was from the last Spider-Man 2 movie. In fact, he was. Sony claims that the PS3 is so powerful it can run the computer generated Spider-Man from the movie in real-time, which may or may not be the actual character from the next game.'
So maybe the graphics i've seen in movies are real then. The x-box 360 movies don't look half as good in terms of graphics.
The ps3 it seems will run better physics than the xbox 360 it seems anyway, even if it does use 3 processors at 3.2ghz