Ok after a long ordeal with this crap, I've found that this is actually NOT an infection, spyware, browser hijack or anything, it's actually a "legit" ad-serving and search cookie by doubleclick.com which is owned by Google.
I'm not sure how this was put into place in my browser and I'm now wondering how many surfers have this because with this crap enabled the search engine referring URL is not google but instead doubleclick.net/.com and my site was not counting this traffic as coming from a search engine. Motherfucker...
Here is an opt-out link I found to get rid of this shit:
http://www.doubleclick.com/privacy/dart_adserving.aspx
Edit: my yahoo listings are also using this doubleclick shit too! What a horrible fucking idea this is, how are we supposed to monetize search engine traffic if people are being sent through this shit?!
More opt-out's:
http://www.networkadvertising.org/managing/opt_out.asp
This is fucking ridiculous..