As soon as MrDSL releases his mixer theme for RC2, I will be doing my best to have it updated ASAP! Hopefully he will release it very soon and I can get to work on it.
As for the Nexus S, if you contact MrDSL, you could see if he'll make the original Mixer theme for your Nexus S. If he does, then I should
be able to get it to work for you. But I can't make any promises, I tried porting this to the Captivate for a friend and I just couldn't get it to work. But since it's CM7, I'm thinking I should be able to get it to work.
EDIT: Mixer just got released for RC2. This'll be my evening project!
Also, is anyone seriously attached to this battery icon? If not I'm going to change it to the battery icon from the new Honeybread theme.
EDIT2: Almost done with the update!
I'll hopefully have it up shortly after noontime(EST).