Yes,
BeerSmith 2.0 will be multi-platform. I have been working hard on it over the holidays but still no release date. Unfortunately it always seems there is more to do on it, but I'm hoping this will be the year it all gets done. Ideally I would like to have it out in time for this year's brewing season (perhaps summer). I am getting close to having an "alpha" version for testing however.
Cheers,
Brad