Mark of the beast concerns aside the idea of an always on, always readable, RFID chipped ID leaves plenty to worry about. When the first chipped passports were shipped back in 2006 someone was able to read passport info within a month and now researchers have been able to take an otherwise normal passport and place fake information on it invalidating the "safety" of chipped identification. That's just the start; WIRED magazine has covered the exploits of individuals who have stolen information from IDs, key cards, gas payment programs and more simply to prove it can be done.
Even if you don't care about the big brother-esque implications of an always transmitting form of identification because you subscribe to the, "You only have something to worry about if you're doing something illegal ideology, you should be concerned by widespread use of chipped licenses.
The Department of Homeland Security is quick to point out that EDLs don't contain any personally identifiably information - other than your unique license ID - but as Chris Paget points out in the embedded video, correlating the information from an enhanced driver's license with an RFID equipped credit card would simply be a matter of finding a suitable location, such as a doorway, and using inexpensive hardware.
The reality is that there is no un-hackable system and "enhanced" driver's licenses would be a potential hotbed for identity thieves. Since the embedded RFID chips would transmit information when asked, Identity thieves wouldn't even need to grab your wallet to get information from your license or credit card. After grabbing your information it's only a matter of effort to create a new chipped ID filled with your info and a picture of your thief enabling them to open accounts, get health care and who knows what else, all without question since the ID is authenticated.
Ideally an enhanced driver's license or future passport will have an on switch so it only transmits when you or someone else applies pressure to a certain point on the card. Barring that unlikely inclusion if you want to avoid being tracked and cloned you better order your RFID blocking wallet today. How many other people can say they have a Faraday cage in their pocket?