"Google has been pretty clear that they are against links that manipulate page rank, whether paid for or not."
The problem is, all links do "manipulate" the algo - it's just the natural ones don't do it intentionally. Google thinks they can determine intent, but let's get serious: nothing could be 100% accurate in determining what someone intended a link to achieve. Heck, when I get a good inbound, I'm thrilled about what it'll do for my SEO. I didn't ask for the inbound. I did absolutely nothing to make it happen. But if you read my mind, you might even think I had deliberately manipulated it.
So like I said earlier, I'm okay with Google banning a company that openly advertises "We'll help you screw up Google's business model for your profit." What I'm not okay with is the punishments Google hands out for any linkage they *think* may not be organic.