A few of the swamis are taking new names. Eventually, all of the monastics will have the word "natha" in their name, denoting we are all of the Nandinatha Sampradaya. This is a similar tradition as in other orders, where "ananda" or "puri" is appended to a swami's name.
We can continue to use the simple titles: swami, acharya and paramacharya when speaking with the swamis. The full, formal names are in this style: Paramacharya Sadasivanatha Palaniswami, etc. Here are the four new names to get used to:
Paramacharya Sadasivanathaswami (formerly Palaniswami)
Paramacharya Sivanathaswami (formerly Ceyonswami)
Acharya Kumaranathaswami (formerly Kumarswami, notice the added "a"

); Acharya Arumuganathaswami (formerly Arumugaswami)