AdChoice is also known as remarketing, retargeting or interest-based advertising and I'm not sure whether you know this already @Sega ; but all these can be done via Google AdWords.
Interest-based advertising is pretty generic in terms of targeting and ads are served based on a visitor's web browsing history.
Your example actually refers to remarketing or retargeting. As I have some experience running remarketing campaigns, one key success factor that I learned is to have different messages in your remarketing banners as compared to your generic banner.
To illustrate this, here's an example (using the SEO company context):
- Generic Banner - Industry-Leading SEO Company
- Banner targeting visitors of your Link Building page - Still Looking for that Proven Link Builder?
- Banner targeting visitors of your About page - John Doe, Awarded Best SEO Practitioner 2013 by XXX.
- Banner targeting visitors of your Request a Quote page - Free Consultation and 10% Off for First Time Customers
Many are in fact doing remarketing wrong by using just one generic banner to serve all targeting options available. It is also worth nothing that CPC is higher for remarketing.