Mario is still playing tennis.
After a hiatus, Camelot is back with more Mario Tennis. So far, Mario Tennis Open looks like more of the same. What was on display at GDC was basic tennis gameplay -- singles and doubles exhibition and tournament play.
The controls were solid, as they have been in previous games. The various buttons are used to perform different shots -- X for simple shot, A for topspin, B for slice, and Y for a flat shot. Hitting A then B lobs the ball and B the A performs a drop shot. Alternatively, you can use the touch screen to perform the moves, which is divided into colored sections that represent the type of shot to hit. It's not really necessary, but it might be easier than the button combos for some people. The biggest new addition is a colored indicator that appears around the optimal position to return the ball. If you tap the same colored area on the touch screen while standing in this area, you can hit more powerful return shots. I didn't see any of the over-the-top stuff that Mario Power Tennis had.
The game includes a new gyroscope-based view mode. When activated, holding the 3DS up in front of your face causes the game to transition into a behind-the-back view, rather than the normal three-quarter top-down view (it also unfortunately deactivates 3D, reducing the effect somewhat). You can tilt to the left or right to change your view slightly. It's an interesting perspective, but having to hold up the system to use it doesn't seem very feasible for long term use.
As in previous games, each character has a their own performance and hit style. The following characters were playable: the all-around Mario and Luigi, technique-oriented Peach and Daisy, speedy Yoshi and Diddy, power players Bowser, Wario and Donkey Kong; tricky Bowser Jr. and Boo, defensive player Waluigi, and Miis. There are also several different courts, ranging from the traditional Mario Stadium courts to a dark and stony Bowser's Castle and a snowy Penguin Iceberg. Others included the bouncy Mushroom Valley, sandy Wario Dunes, DK Jungle's wooden court, and a carpeted Peach's Palace.
The graphics were super crisp, and all the basics were there. Just those with the addition of online play would make a good tennis game. It remains to be seen what other sort of trademark Mario additions will be available in the other modes, but so far, it's another competent Mario Tennis game that doesn't stray very far from its predecessors.