As a general rule...
...any of today's modern bindings will do just fine from a safety point-of-view. However, if you're gonna' be playing mostly in the park, pipe or moguls, a binding with a lot of elasticity will be your friend. Elasticity is basically the ammount of travel a binding heel/toe piece will have before it actually releases.
As long as you stay within the elastic range of the binding, the binding will actually keep you engaged vs. releasing pre-maturely. Once the forces return to normal, the binding will re-center you. Also, a high-elastic binding will allow you to use lower DIN settings, which can be safer since crashes/falls are common in the bumps and the park.
Look's turntable-design has been the standard in elasticity for decades. They also feature great shock absorption and extremely easy entry/exit as well. The current turntable line is called Pivot. I've used Look turntable bindings on several of my skis for years and cannot say enough how well they perform. Again, it's not that they're better per se, it's just that their toe/turntable design offers features that other binding makers do not. Check out Dynastar's web site for more info and pics
...you can get them for cheap at many shops or web-sellers.
If you want a binding with true park/pipe cred, look at Line's bindings
...they're pretty innovative in that they can be swapped from ski to ski and they, too, feature a turntable-heel. I haven't heard/read too much on them in terms of real-world performance, but if they're good enough for Line's pro team, they're probably tough enough for anyone else in the park.
Right now, I'm using Marker Piston bindings that came with my skis. I really like them and how they make my skis work and feel. But, if I were on a ski that did not
come witha specific binding...I'd most likely be on a Look Pivot turntable.