http://eg.nttpub.co.jp/news/20061003_03.html
1,5 Million units sold in about half a week... :-O
I've never played any of the Pokemons, but perhaps someone here can explain the concept?
I guess you a couple different Pokemon that can fight against other Pokemon, but is there anything else to do?
You fight lots of battles, but in contrast to standard RPG stuff you don't get your own hands dirty but let your pokemon do all the actual fighting. You start with one and can capture more ("wild" pokemon) in random encounters. There are usually 150 or so different pokemon in a game, and they have very different characteristics (elemental strengths/weaknesses, that kind of thing).
Fights are usually one-on-one but you can swap out pokemon mid-battle. I think Ruby/Sapphire introduced tag team battles where each side has two pokemon out at once, but these are very rare scripted encounters.
Your character doesn't level up. Your pokemon do level up, by gaining experience points in battles. They are all independent, so the ones you don't bring out in fights will stay weak/not grow stronger.
You can "own" hundreds of pokemon but you can only use a very small team (6?) for battles. You can swap those out while in a town.
The basic drive of the game is finding/building up a team of pokemon that works well against the enemy pokemon you're currently facing. That's a moving target because as you go through the game world, the prevalent enemies change and your team composition must be adapted.
The game worlds and lore are always very focused on that whole pokemon battling stuff. There are pokemon battle arenas everywhere, "pokemon trainer" is the equivalent of "rock star" somewhat, so everyone in the games wants to be one etc. There is approximately nothing else that matters, but it still works very well.
The games are actually great fun and well made. Success requires not only level grinding but also a lot of strategy. They also work very well as entertainment for grown-ups.
