If I were you I would go to Faculty Night unless it is a class you feel you'll really need to attend the first lecture. Usually in the first lecture you are given a course outline and go through basics/introduction material that you can catch up on and/or get at the second lecture. Remember, first week or so is add/drop period so students will be leaving and joining the class within the first 2-3 lectures. Also, my guess is that a lot of your classmates will be going to faculty night as well.
Faculty Night is a fantastic way to meet others in your faculty and socialize/network. It is a great time, and for a first-year student is something I wouldn't want to miss!
If you do decide to not attend faculty night, hopefully we'll see you out at the MacInsiders Social next Thursday... you'll be able to meet others in your faculty and network there as well!