There are several distinct camps-

Camp 1- the wait and see what the fix is and keep the car. Only a few states actually link re-registration to emissions recalls so most drivers can avoid it if they want
Camp 2- the unaware of the entire situation and its an appliance i like. The car will be fixed when i get a letter and i will take it in and not even notice the difference if there is any
Camp 3- i was betrayed by VW and now i want money and lots of it. Everything that ever went wrong in my life can be attributed to VWs nefarious evil schemes

Depending on which camps you have your feet in you decide from there. The value is only slightly lower at the moment. The 2012 TDI we bought 1 week before the scandal seems approximately about 500 to 1k less in value, a marginal hit. Once they come up with a fix the value will climb back up, TDIs traditionally hold their value decently.

Doesnt really matter as we bought the car to drive for long term. They are quality cars, so if people do fall all over themselves to get rid of them in the "betrayed by VW" camp, they will be snatched up quick by enterprising buyers.

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