Thinking like this is bad for your business.
Google does not have anything against porn. The only Google product that does not support porn is Google Adsense.
If your site suddenly fell in ranking due to anything that Google did, it is Google improving how they rank sites to provide better search results to their customers. It has nothing at all to do with porn.
For example. If you had an Olivia Wilde tribute site, full of photos and articles about Olivia Wilde, proper tags and good content *about* Olivia Wild, Google would like you because you are providing exact the content someone searching for "Olivia Wilde" would want, and especially click on.
If other site owners ALSO agreed and linked to your site, Google would like you even more, and give you higher ranking on search results.
If those back links are from useless pages, scripts or other "bad" things, Google will lower your rank. IF your site is not relevant to the announced or advertised subject, your rank will drop again.
If your site was doing well yesterday and poorly today, it may be because Google has changed how they rank sites, or they found something they don't like.
I was talking to our Google ad rep yesterday. We buy Google Adwords for our site,
www.2Much.net, and I asked him if it was ok to link to a porn site, then got on to the topic of porn sites in general. He said just what I said above. Google only cares about delivering quality search results to its customers, porn or otherwise.