Google should still be able to see the webpage the links originated from.
Like Anthony said, it's a grey area. To the best of my knowledge Google has been consistent in saying all paid links should be no followed, but in the real world this isn't what happens. I know of many sites in my niche paying a lot of money to advertise on a site that grants them followed links. The question becomes do you join them, or do you do what Google tells you to do?
That's up to you, just know there are risks, and you never know what Google is going to decide to do next.
