Herbalife still is a 'real' business. Ackman would like you to think otherwise but it still is. The whole thing might be a point against short sellers.
Another famous short seller, John Hempton, responded to Ackman's short with a very public investment case for going long Herbalife (he argues it's a kind of social club with supplement sales attached as dues). Short sellers definitely don't bat anything close to 1.000 though.