While still in her apartment, Miranda is wearing a dark blue fur scarf. But when we see the girls walking together, Miranda's scarf is now a mixture of blues and browns with a spot of red.
The "Dear Single" ad in the Romeo & Juliet flyer that Carrie gets in the mail reads, in part, "about the person your seeking". The contraction "you're" should have been used.
Carrie asks Big about his age, but in the previous seasons she knew his age, she could have known it without asking.