My wife and I are planning to take the eurail (5 country pass) starting in Paris then to Amsterdam, Luxembourg, Berlin, Munich, Zurich, Geneva and finally Italy.
Our question is...if we want to go back to France (Nice) after Geneva, will this be included in our 5 countries, even if we are not visiting France consecutively?
yes
However, do do your homework. With supplement fees, and limited pass access to some trains, the days of a rail pass being an automatic good deal are long gone. Sometimes you have to work very hard to make a pass pay.