mr lesbo is disturbingly anti-nintendo, but confusingly has a major problem admitting it (note above post).
i'm very much pro nintendo, and make no attempt to hide it. that doesnt necessarily mean i hate or even dislike the other systems, they just dont interest me. i'm indifferent towards them. i'm always quick to point out their plusses, but quick to explain how, in my view, the nintendo plusses outweigh theirs.
the reason i currently have a gamecube is really because i started out with NES. i've had every major nintendo system since then and have simply stuck with the company.
part of it is, of course, blind name-branding loyalty. i drink coke over pepsi for partly the same reasons.
but, mostly, its because i enjoy nintendo games better. much better. my favorite games of all time have always been nintendo games.
really, in this generation of consoles, all three major systems are identical. yes, there are differences us game freaks will notice, but... for all intents and purposes, the ps2, gc, and xbox all have the same capabilities.
in the same thought, most every game (80-85%) on the market is a third party game that can be played on all three systems.
so, since all three systems are very similar and all three have mostly the same game lineup, the major differences between the systems are whatever they have exclusively.
nintendo systems come with nintendo games. marios, metroids, zeldas, karts, rogue leaders, star foxes, eternal darkness(es?), smash bros, etc.
the weight and quality of the above games is, again in my view, by far and a way the biggest determining factor. more than enough to keep me in the nintendo field. if i couldn't play wind waker or prime, i'd be a miserable gamer, and missing out on 2 of the greatest games of all time.
and there's my reasoning!