No I mean like in wifi you say "I will trade a [Pokémon] for a [Pokémon]" and wait a while, when somebody responds you trade with them.
That's what the Global Trade System is. You list the Pokemon you're looking for, and what gender, level, etc you want it to be, and then just leave it for someone to reply. You don't need friend codes for this, but you can't communicate with anyone through it. It does seem to be rather effective at the moment though, like I mentioned before, I was able to get a Chimchar within minutes.
I'm really loving the game so far, it's definetely the biggest game by
far. They brought back a lot of great features from the older games, and some really cool new ones I never even knew about. I'am a little disapointed they went with the "classic" Pokedex, over the far improved encylopedia style we saw in Fire Red/Leaf Green. But all things considered, there's very little to complain about.
Oh, and while I was exploring Iron Mountain, I came across a shining Graveller.

Has anyone else seen any rare coloured Pokemon yet?