Many places will be closed, and it won't be the sunny, Italian Riviera. Depending on your tastes, it could also be the perfect time. Instead of being packed in a snakelike crowd, you'd have the CT almost to yourself. If you want to have an idea what the CT could be like when you have it to yourself perhaps read, "Beautiful Ruins" by Jess Walter. Complete fiction, in a fictitious town, but a reasonable facsimile.

Rick Steve has been so successful, hats off to him, that the places he sends you to "through the back door," are now generally overrun with tourists. If you've already, "been there, done that," almost any touristy place he recommends, including the CT, is better in mid-November than in the summer.

Having said that, if you are new or even relatively new to travel in Italy, and are trying to have the usual, awesome CT experience, I wouldn't go there in November because it will be a lonely place, and will not be what you were expecting. Other places will be better.