As to whether you have to have Steem vs Steem Power vs. SBD, I'm not sure how that is going to work. The white paper is unclear.. No specifics on how to claim the tokens either.
I am hoping that say.
Example. If I had 10 SBD , 100 SP and 10 Steem, that they can calculate a total value of what the equivalent SBD in my wallet would be at the snapshot of 185,000 (If that is what they are using as a base measurement to divide and distribute Vice tokens)