This is great!!!
First is the gameplay. The game obviously has the rules of baseball. Before I played the game, I didn't know the rules of baseball, until my brothers taught me, and I played practice mode. I thought it would take me time to learn how to play the game, but it only took me about 10 minutes. It's best to play the game multiplayer, because the opponents might be a bit annoying catching most of the hits you do. Hitting big homeruns feel cool. Some minigames are cool too, like batting Bob-ombs to light up the night with fireworks, and more...
The graphics are great. In the entrance movie they were great, and during gameplay they're good too. The graphics of the audience are a bit worse, and in challenge mode when you walk around. Great graphics overall.
OK the sound. The sound of some batters charging up their shots sounds a bit dumb, and the way the referee Lakitu does the calls sounds a bit silly, but I love the sounds of those fireballs and powerful shots.
In all, this is a great game. Buy it if you're a Mario fan (like myself) and like his sports games.