According to this report from the Daily Swarm, The suit names R.J. Reynolds Tobacco Company (the parent company of Camel cigarettes) and Wenner Media (the publisher of Rolling Stone) and claims the companies misued the artists names, misused them for commercial advantage (right of publicity) and takes them to task for unfair business practices.
The suit goes on to accuse both the cigarette company and the magazine of engaging in "despicable conduct" that was "illegal under settled, unambiguous California statutory and common law." The lawsuit demands Rolling Stone publish an admission that the artists' names were used without consent in a spread equal in size to the original ad, as well as seeking actual and punitive financial damages. (Under California law, this could conceptually amount to $750 per issue of Rolling Stone, per band, or a whopping $195.3 billion
Budding lawyers and/or masochists can check out the entire PDF version of the complaint here.