Go ahead and place this story in the quirky, crazy little things that happen on the internet bin. Google isn't perfect, they'd be the first to admit this, unfortunately their errors are readily apparent to millions upon millions of people on a daily basis. For those searching "swtor.com", the popular MMORPG, you might notice an odd thumbnail image for the link that takes you to the game's launch documentary page.
There have been instances of video thumbnails displaying incorrectly, both within Google's SERP's and on YouTube. However, for a term as popular as "swtor.com" and an image not only off-topic but hilariously porn related, you can't make up stuff like this. Enjoy it while it lasts, I'm sure the problem will be fixed soon.
These proceedings haven't changed my thoughts towards the game.