YES there is a new refrigerant being introduced. #R454B / #RR32
There are 2 new refrigerants actually.
The first is R454B. This is the mainstream refrigerant most manufacturers are going to use. the second is R32.
R32 is actually a component of the R410A already in use today. So far it seams only 1 major manufacturer is going to be using the R32 and that is the Daiken/Goodman brand lines.
To date, the R454B has a lower environmental impact and should be around longer than the alternatives.
Just in case you are wondering, NO, neither of these refrigerants will be a drop in for your existing R410A system and Yes, R410A will be around for the next 15 years so no need to panic yet, just prepare.
More on this topic throughout the year as we move toward the NEW refrigerants.