Continuity mistake: Tony, Carmela and AJ are meeting with AJ's college tutor. Partway through the meeting AJ is asked to leave. When AJ stands up he is wearing beige coloured trousers, but as the shot changes to show him walking out the door, he is now wearing black trousers.
Other mistake: In the scene where Paulie Gualtieri goes to confront "Feech" La Manna at the bakery concerning the landscaping feud, the clock on the wall doesn't match the time on La Manna's watch or the clock on the wall behind La Manna's desk. The big clock says 11:55 while the other two say either 2:45 or 9:10.