nah, they have a roadmap but it's not dated. I'm thinking YouTube was used for Beta because WildSpark is a Google Chrome extension and Google owns YouTube so it was easy. According to their own description of WildSpark: "Synereo’s solution allows users to send currency directly to content creators, regardless of the publication platform, as well as be rewarded for helping others discover great content." 

That "regardless of the publication platform" tells me it will work on more than YouTube when finished....