[quote=marcopolonian]How will the whole evolution-by-trading work out? Is it caused simply by physically swapping Pokemon, or are more intricate trading machines required?[/quote]

Now, this is something I'm not completely sure of myself. Trading machines are not necessary, that much I can promise. I'd probably make it work like level evolutions, or someone else has to train the pokemon for you for a bit before they'd evolve. One or the other. If you have any input on this, feel free to put it in.