My friend will be in Florence from December 23 - 27. I am helping him plan the trip. Is the academia museum closed on Christmas? Christmas Eve? How about visiting The Vatican...is it closed on these days? I am sure The Vatican is closed on Christmas Day...but is there anything special to do in Florence or Rome on Christmas Day?
Tons of info on what to do in Rome at this site: http://www.roninrome.com/ Search for "Christmas". Not all the info will be current but it will definitely give you ideas of what kinds of things are available to see and do.