Sifaka World announced today that its wildlife-preservation-themed virtual world had reached over 100,000 signups in the time since its soft launch in December 2008. Based on its growth, the world is prepping to launch a subscription service in March, with a portion of the $4.99/month plan donating 10% to wildlife preservation and the $6.99/month plan donating 30%. The virtual world has already partnered with the Cheetah Conservation Fund.

In addition to donating money to the Cheetah Conservation Fund, Sifaka will also begin including content from the organization to educate its users about wildlife preservation, working in conjunction with Cambodia Wildlife Sanctuary.

Sifaka uses the Electrotank Universe Platform (EUP) and ElectroServer 4 and was co-developed with Two Animators! LLP.

Sifaka was founded by Creative Director Garrett Box, CTO Brian Yennie, and CEO Deborah Moore.

“It doesn’t get better than this. Sifaka World marries the best in virtual world technology with fantastic art, original characters, and a socially responsible corporate mission,” Yennie said in a statement. “This is the company I’ve always wished I could create. What’s in Sifaka World right now is just the tip of the iceberg in terms of what we have planned for the future.”

I’ve said it before, but the kid’s space for virtual worlds is already crowded and the green niche is getting swamped. It sounds like Sifaka is off to a good start, though, and building a strong base without much, if any, marketing.