My take: ethical marketing is where you are trying to serve the customer. Unethical marketing is where you serve yourself at the expense of your customer.

One problem, of course, is that advertising and marketing people, being what they are, will almost always tell you they are trying to serve the customer. (And they generally believe it.) To tell the good from the bad, you will have to use your own moral compass.

The bigger one, though, is that it's an arms race. In a perfect world, nobody would push anything. You could just release your new product; those hungry for a solution would find it and become your customers. Sadly, those people right now are being aggressively manipulated by your competitors. They will never hear about your product. If you want to succeed, you will have to get your hands dirty with actual marketing.

Personally, I bridge the gap by asking myself three things:

1. Are we legitimately creating value for our customers? Would they be better off using our product?

2. Is our approach to marketing reasonably ethical, and at least no worse than the competition?

3. In the long term, are we acting in ways that will reduce the arms race, or at least make it no worse?