Jason,
It's a ficus, which variety I'm not sure. I guess my reason for the love of cascade bonsai is the wild look it gives, imitating what you would see in the mountains. That and the fact that you don't see any really good ones because most people just take a juniper whip and bend it over and say it's a cascade.
Here's my two other cascades, a JBP that I had nothing to do with as it was purchased as a cascade, and a procumbens juniper that I started myself.