I suspect the first enforcements will come for multiple violations such as flying in a reckless manner over No Fly Zones and without a registration. How will these enforcement actions come you ask? Will FAA deploy teams and Units of Drone police. The answer is no, no new units, just some guys at FAA monitoring YouTube and other social media for people who post video of their clearly reckless flights. FAA will then contact them for proof of registration. Once the poor sap is snagged in the no registration trap, the FAA won't even bother trying to prove up a "reckless" case and simply cite and fine the offender for no registration. Large initial fines will deter people from posting YouTube flights that reflect overt violations of FAA guidelines and restrictions. Once illegal flight videos disappear from YouTube etc, later enforcement actions will be based on wreckage found in areas that are overt violations of FAA guidelines but are properly registered. All other enforcement actions (those where the aircraft and operator and unregistered) will only come from serendipitous events that allow the FAA to gain evidence of illegal flights and the identity of the operator. It is my guess that only a very small number of these last types of enforcement actions will ever happen.