Separate states and Homeowners deduction

Thank you in advance for your assistance. My wife is retired and we purchased a home in Florida. We are both from NJ. We have been filing, "Married, Jointly" since forever. She will soon be a Resident /Domiciled in Florida. I will remain in NJ working and living in an apartment. The question:

1-What are the benefits of filing, "Married-Separately"?

2- Would she be able to deduct the Real Estate Taxes? 

3- She is retired and has no income, so what would be the purpose of Filing Separately? To take advantage of the Real estate deduction that would not effect her anyway?

4- In NJ, there is no Real Estate Deduction for a 2nd home. So should we just file Married-Jointly since there are no benefits until I become a Florida resident?