Stratos, Swyp, and Plastc will offer tokenization eventually, a feature that masks your credit card's identity for each transaction, preventing your true account number from being exposed during a credit card data breach. (Plastc and Swyp plan to add this feature as an update after the initial launch.)
These cards can be updated with over-the-air updates, so expect more features to be added as smart card makers look for ways to make their product stand out from the rest.