I still don't think expiration dates are necessary or wanted. I would rather have less currency in circulation, than have my bitcoins randomly expire because I forgot to redeem them by a certain date. I HATE expiration dates on things. If I get a gift card, I want it to be good for as long as I live. Same with gift certificates. Expiration dates are frustrating, obnoxious, and I would never purposefully buy something with them. I'm too forgetful of a person to buy money that expires.
I also hate when gift cards expire, deactivate, or when their value decays to nothing. Redeeming or reactivating a gift card is a pain. You have to either go to the right store to spend it or mail some forms to the Vogons. But, with something like BitBills, you can redeem, and simultaneously void, the notes yourself. All you need is the means to cut them open and a camera.
I expect that we will eventually have multiple printed bitcoin implementations and people will choose the ones they like or not choose any. As we all know, bitcoins work fine unprinted.
