Craz Z is right any kite can be used for riding snow. Lableling a kite "snowkite" is often viewed by "dyed in the wool" snowkiters as little more than marketing.
However, there are some kites that were concieved as "snowkites" and have been known as such from the beginning. Again as Craz Z points out, some have been around for 10yrs. The suitabilty of a given kite for snow used depends largely on the environment, the type of snow use and the users's demands. "Run what you brung." Usually works for most people in a winter kiting situation
Some kites are better suited for a wide range of snow use than others simply by design, features like long leaders to reduce risk of edge slash, colored lines, flaps in the dust outs for example, make some kites better suited than others. But kites without those stock features, can be easily adapted.
The Leopard looks to be a higher AR than the Frenzy. More like a Summit or Montana 8. We'll get a demo here at some point when the size want for our demo quiver becomes available and see how the kite performs. We have the Lynx in demo and it's a pretty sweet wing.
Really IMO getting the most out of snowkiting relies as much on you skill set as a kiter, skier or snowboarder and the rest of your equipment (skis etc.) as it does on the type of kite you have.