Over 1/4th of the owners of PS3 bought Gundam Musou. That's not too bad. Also, it does matter that all the Gamecube games were first party because 3rd parties want to make money. Looks like all the PS3 games selling great in Japan are 3rd party.
Resistance is not a killer app in Japan because it's a FPS.
Comparing these 2 random console launches doesn't really say much. Gamecube had a great launch lineup but ended up 3rd. PS3 could have a bad launch lineup and end up 1st or 2nd. Why not compare to the xbox or xbox 360 or the PS2? Why just 1 console? Let's compare them all. Is there some kind of trend to the data? So far, no.