There is a highly interesting discussion unfolding at the feasta.org website. It deals with the discussion about paper currency and virtual tokens.
Initially, the LQN had been proposed as an electronic system only. Such a system allows different tweaking, as there is the chance to adjust the currency supply to the economic activity level.
After the auspicious meetings with both the Kilkenny Council and the Kilkenny public, the wish for the introduction of a paper version of the quids has been postulated. The main driver for this being an increased identification and acceptance through tangible units, as well as broader integration of potential members with no interest or reluctance to adopt electronic devices.
The project team has taken up this new proposal very seriously, as it recognizes the validity of its advantages. Several issues need to be addressed, like the costs of production, introduction and distribution/removal, forgery, as well as coexistence issues with the electronic version of the quids.
There is an interesting discussion thread at the feasta website which deals with this subject. You can follow it here.