My experience was similar to Shannon's, except I have Time Warner Cable. They initially (ambiguously) claimed to be Time Warner until I mentioned Evergreen Sales, at which point the rep clarified his employer as Evergreen Sales. The call was offering a $5/month 30-day evaluation upgrade to their "Turbo" package, a speed upgrade essentially.
The rep also provided this number as one I could call with questions - 866-408-2225
. That number is Time Warner's "Action Line", which I have used in the past and is legitimate.
It seems this is a legitimate marketing firm that is being used by various telecoms. That being said, I received three calls from this number prior to my conversation today which were dropped as soon as I answered. All were to my cell phone, which is what I have listed with Time Warner.
BOTTOM LINE - If you're being called by this number, your first course of action should be reviewing your Service/Privacy Agreement with your ISP (Comcast, Verizon, Charter, etc.) and verifying their policies on providing your contact information to outsourced/contracted marketing firms. If you can determine that you didn't sign away your privacy when you signed up for Internet service, I recommend contacting your ISP directly.
If you're having trouble getting a hold of someone who can resolve your issue, The Consumerist has a useful guide on getting what you want from a business, including a directory of Executive office numbers for when things get ridiculous.