You can strike your opponent using the X button, or grapple with the A button. Moving the analog stick in different directions will pull off various hits, kicks, slaps and holds. The Y button allows you to run, rebound off the ropes and climb turnstiles to jump on your opponent.
Wrestle Kingdom favors a "work the body" style of gameplay, where you can focus on various body parts to wear out your opponent and make him more vulnerable. There's also a "voltage" meter that builds as you perform more impressive moves. Once your meter is filled, you can hit the A and X buttons together to perform your wrestler's finishing move.
The character models in Wrestle Kingdom look quite realistic, and you can almost feel the sweat dripping off of the wrestlers' mullets (mullet-sporting wrestlers aren't just an American thing, apparently). The arena we played in also looked quite nice, with polished hardwood floors surrounding a standard wrestling ring.
Wrestle Kingdom is currently slated for a Japanese-only release, and given the Japanese-licensed wrestlers, I doubt we'll see a US release, at least in its current form.