Yup...you got that right. EM games are taking a hit and it will keep working its way up the chain as new technology works its way into the consumer product. In an ideal world our games value would stay flat but even with inflation. But thats not going to happen due to technology making the previous version of games obsolete in the eyes of the consumer. This is a "throwaway economy".
Someday soon the DMD games will be old technology too and it will reflect in the value of the used games. Stern will have to get on the bandwagon eventually to an LCD, but they will not be the factor that they used to be in the pinball world if they do not regain the confidence of the consumers by finishing the code on their games. For what people are paying for new games these days they expect a finished product. Or at least they expect that it will indeed be completed later.
It takes more than a bunch of flashing lights to make a game a success in this market that is selling primarily to well informed home use owners. A bunch of flashing lights might make a game a success in a bar, but thats not where the majority of new games are going anymore.