Fat Princess is probably just there to have someone rep PSN.
Also, regarding the whole "growing up with Nintendo vs. growing up with Playstation" discussion, I personally grew up with both almost equally. My family owned a NES that I remember playing Super Mario Bros./SMB3 and Duck Hunt on all the time when I was like 5 or 6, and I remember playing SNES games like Super Mario World, Super Metroid, ALLTP, etc. at my babysitter's house with all the other kids there when I was really young. I also remember playing N64 games all the time at my best friends' houses, and to a lesser extant PS1 games (I only knew one person with a PS1). Then, at the PS2 launch, I got that for Christmas and it was the first console that I owned myself other than Gameboys, so I played the shit out of Ratchet, Jak, and Sly games. I also ended up getting a Gamecube a few years later.
So anyway, boring life story boils down to Nintendo and Playstation characters being equally memorable to me, since I'm only 20 and young enough to actually have been a kid when playing PS games.
That's one reason I think a lot of the media will be pretty down on this game. Games like this and Smash rely a lot on invoking nostalgia to grab interest, and a lot of game journalists are just too old to feel that same nostalgia for Playstation that they do for Nintendo. They're from a different generation and I think a lot of them will have a hard time accepting that there are people out there who were 8 years old when they first played Playstation, and that it does carry a memorable feeling of nostalgia for them.