There are several threads at the Google Webmaster Help forums with Google users saying they are seeing ads on the Google home page, but the ads are specific to adult sites and pornography.
Here is a screen capture of what one user saw but cleaned up a bit:
One thinks it had to do with an extension he added to his browser related to a "Mario Game." Others believe they downloaded some weird malware or virus.
If you see this, you can know it is not something Google wants on their home page and you likely installed a virus or malware on your computer.
It is just upsetting that there are several people reporting it in the forums because that means there are likely more affected.
