Ok, cool. Just makin sure I was clear. 
Is this noticeable immedeiately after shutting off the engine? or do you mean after 2-3 pedal applications with the engine off?
If it's immediate I would likely say the booster is leaking. If it's after 2-3 apps I would say that is pretty normal. 
Maybe see what happens if you hold the pedal down with the engine off and see if it bleeds off completely like that. 
Happens right after i turn the engine off....
and, when I am on the brakes still rolling and turn the engine off, the get worse also.
Id say its bad. Dammit
