From the Club Level post, post #7, of this thread.
Tower Club = 14th Floor = Access to both Tower Club Lounge and Atrium Club Lounge
Atrium Club = 12th Floor = Access to the Atrium Club Lounge
The Tower Club has a total of sixteen rooms: Five Standard rooms (two King and three Queen) and eleven suites comprised of One and Two Bedroom Suites, a Vice Presidential Suite and a Presidential Suite. When booking a Tower Club Queen room, the confirmation will read: Standard Club Level - Queen ("CY"), There is no guarantee of a Magic Kingdom or Bay Lake View with a Queen booking, however, both King rooms face the MK. When booking a suite, you will be assigned either a Bay Lake or Magic Kingdom View. For Queen and Suites, you can request a view, though it can't be guaranteed.
~The lounge on the 12th floor (Atrium Club) is bigger and has more seating then the 14th floor Tower Club. Three Standard rooms were used to build the 12th floor lounge. There are three balconies on the MK side for Club Level guests to watch the fireworks.
~The 14th floor room and lounge balconies are bigger than the 12th floor balconies.
~Both floors serve the exact same food for breakfast, afternoon snacks, 5 PM hors d'oeuvres and 8 PM deserts & cordials. The 12th floor Atrium Club rooms are marginally less expensive than the 14th floor Tower Club rooms.