This became apparent when I was watching this Game Sack episode(I think its sponsored by Sega-16?):
http://www.youtube.com/watch?v=CRnam89J0xI
Flagship first party racers:
Sega: Kinda hard to determine. Virtua Racing, Daytona, Sega Rally.
Sony: Gran Turismo.
Nintendo: Mario Kart.
Going back to 16-bit era, black Genesis vs. purple SNES. Sleek Sonic vs. fatass Mario. Blood vs no blood.
So in your opinion, do you see Nintendo as, "just for kids"?
I remember in the high-school days, I skipped out on the Gamecube because it wasn't getting GTA(perhaps Rockstar didn't see that demographic in the Gamecube).

