It will be interesting to see what happens to Mozilla's marketshare moving forward, given the publicity this has received.
What they don't seem to understand is that playing politics with popular issues is a double edge sword. As an earlier guest pointed out, management should have examined the PR implications of hiring Eich prior to making the decision. If his support of Prop 8 can reasonably seen as damaging Mozilla's image, his ejection on the basis of holding a contrary viewpoint is equally as damaging. After all, voting numbers on this issue clearly demonstrate a larger segment of the population does not support same-sex marriage. In short, you alienate a large portion of your customer base either way you cut the cake.
This in mind, the employee who initially took this Prop 8 issue to social media and turned it into a story should be fired. If you're willing to generate negative press for your firm just to make a public political statement, or you aren't intelligent enough to understand the PR risks of social media, you're a liability. As advisable as this would be for Mozilla (even though it too carries PR risks), I doubt it'll happen. To paraphrase an old saying, they've already burned the witch.