Over in Germany, we don't have tracked individual offers yet – but we are damn close. This isn't completely new either – the mobile app is about half a year old, and the custom-cupons at the counter is about four years old now. It obviously has some benefit, otherwise it would have been discontinued by now.
1) Individual cupon offers via mobile app – although currently there is no personalization algorithm behind them. I don't expect this will be too successful unless a personalization algorithm runs in the backend.
2) Cupon which you only get when returning bottles at their store – not sure how personalized these are, but they are obviously only available to drink consumers.
3) Cupons which are printed based on products related to what you purchased – you are handed them along with the receipt. These may work well to reward returning customers and encourage them to try new products, without crossing over into the personal data mining sphere but using aggregate data instead.
Supermarkets Try Customizing Prices for Shoppers
Supermarkets are mining the data from their loyalty card programs to adjust prices for and make marketing offers to individual customers.