[DS] Pokemon Diamond and Pearl

The game's the same. Fight battles, get badges, catch 'em all.

The 3d world is a very nice touch. The music has gotten better in most cases. The effects are about on par with a DS game. Kinda disappointed the Poke sprites are still 2d w/ highlights, instead of 3d.

Using the touch screen for battle is a non-issue, as you can use the a/b buttons easily. However, the reward of the Poketch (pokemon watch) with a multitude of interesting functions works off the bottom screen when not in battle. Clock, calculator, pedometer, health meters, and additional "mini-apps" that you can "upgrade to" as the game moves on.
Also, you need to use the touch screen for a few mini-games, as well as for importing Pokemon from older GBA games (Emerald, Sapphire, Ruby, Fire Red, and Leaf Green).

There aren't quite as many "new" pokemon with this game, but there's a lot more pre- and e-volutions of older creatures.

You need to get the first badge to enable you to trade with other D/P games.
You must beat the Elite 4 to enable you to migrate/import Pokemon from the GBA games.

Playing "repeatedly trade the starter trio" has a time block to it, as it takes at least an hour to get to the first gym.

It's fun spinning through the Pokedex as if you're spinning the Price is Right wheel.

Online trading is a great new addition.
There's two ways to go about it -
either you trade directly with a friend (via Wi-Fi or over the internet, both of which require you to share a game-specific Friend Code)
You deposit an unwanted Pokemon in the Global Trading System (GTS) to be sought out and traded for a Pokemon of your choosing by folks all over the world. Drawback is you need to have seen the Poke' you want to trade for, and you can't search to see who wants to trade for what you're offering.

It's fun, though, and strangely enough the first I've ever finished (and I've played Red, Blue, Yellow, Gold, Silver, and Crystal.)