Updating Smart playlist in I Tunes

[vashaun jones]

Listers I created a playlist in I Tunes that pulls all newly  
downloaded podcast to that playlist, but I wanted to know if there was  
a way to remove items that have been played in order to make room for  
the fresh stuff. In other words I want a way thats automated and smart  
enough to update itself instead of me constantly having to change the  
parameters.