I think cbhl's point is perfectly valid, in the presentation of the feature, Apple states that about half of people leave their phones w/o a PIN. Touch ID is for these people and in general will make unauthorized access to iPhones more difficult.
Touch ID is optional, if a user feels particularly concerned, about legal implications of this, it is perfectly valid to revert to a passcode. I am glad that this article/discussion exists though, it is good to know what risks may exists using new security systems.
[Edited to add: just read somewhere else that after 48 hours of inactivity or a reboot, user must re-enter passcode before fingerprint will unlock the device. This would seem to protect from the case stated in the article.]
Touch ID is optional, if a user feels particularly concerned, about legal implications of this, it is perfectly valid to revert to a passcode. I am glad that this article/discussion exists though, it is good to know what risks may exists using new security systems.
[Edited to add: just read somewhere else that after 48 hours of inactivity or a reboot, user must re-enter passcode before fingerprint will unlock the device. This would seem to protect from the case stated in the article.]