I forget exactly when this slip-up occured, but it is when Jameson, or his assistant is laying out a front page for the Daily Bugle. The huge headline says something like Masked Menace terrorizes city, but in the upper right hand corner of the paper it says "yankees flop in home opener". A few scenes later, Peter Parker is at his uncle's grave. There are leaves on the ground and bare trees all around. Home openers occur in the spring, not the fall. Could be a slip up, or a huge leap in the time line of the movie, but nothing points to months passing.