As far as i can make out from UK magazines all the variants of the MP3 will be the LT versions, wider front track to allow riding with a car licence in certain countries.
Also, there will be a limited run in 2014 of the Fuoco, again LT only.
This is in Europe, not sure of their US or Oz plans.
http://www.piaggio.com/piaggio/INT/en/MP3.html#main
So to answer question, your dealer is right and wrong. The 500 as we know will no longer be produced, but yes, the 500 will be produced in LT version!!!!!!!