The way i see it, the each season of the Sopranos is like a 10-13 hour fiilm, to tie up all loose ends (relationships between characters, the russian, NJ Vs NY, Furio, Ray Curto etc etc) in a 3 hour slot would be stupid.
Five seasons have proved to me that the Sopranos is a brilliant TV programme, the change to film would be very very stupid. All due respect