I guess I'm very late to the party... because I'm late in an LTTP thread! XD
P.N.03 is one of those games I can pick up anytime and just play for fun. Not for goals, not for achievements, not for story, not for unlocking anything. Just because of pure gameplay fun.
People who complain about the controls just can't get used to them - because when you do, there are few games with such precise and exact controls.
The lack of variety in the backgrounds is no problem for me, because I don't look at them anyway. There are other, far more important things to look at in this game! That is, enemy patterns and Vanessa's slightly flabby ass:
http://www.youtube.com/watch?v=SlW4TIj9ghE
Her ass jiggles surprisingly much... which is not to be confused with her ass wiggle that she does all the time when she fires her palm shot. What you can see in that video is jiggle, not wiggle.
As some people here have already said, P.N.03 is like a classic space shooter, but with a human in 3D environments instead of a ship in 2D space. Also, I think there are few games that have been so misunderstood by media as P.N.03, and it also goes to show how false expectations can damage a game.
If Treasure made this game, I'm actually quite sure it would've gotten better scores, because:
1) Who cares about story in a Treasure shooter?
2) Who cares about the backgrounds in a shooter? You never have time to look at them anyway.
I'm not saying it's the best game ever, just that it deserved more like 8/10 than 5/10. Also, this is the shooters' equivalent of God Hand. Simple, great games that only focus on gameplay and challenge. And also in P.N.03's case, Vanessa's soft rear end:
Of course, her ass always gets the attention when this game is brought up, much thanks to that infamous gif (which is actually an animation straight from the game). I still remember the first time I unlocked the Papillon suit... wow... there's something about her ass that is so real and not like other backsides in games. Maybe it's the ample size and the fact that it actually jiggles quite a bit. That's not very typical of a Japanese game!