Super Metroid is still talked about because of the organic nature of the game. Instead of just mindless enemies running left, the game presents a natural ecosystem to play with. Probably the most remarkable thing about the game is how skills are learned organically from the planet's wildlife; this article explains really well why it's still ahead of its time: http://supergametheory.wordpress.com/2011/10/23/super-metroid-and-the-will-to-power/