EPA's ban on R-22 (Freon) refrigerant starts Jan 1, 2010

As of January 2010, R-22 refrigerant, a HCFC (hydrochlorofluorocarbon), will no longer be manufactured. Homeowners may have various types of appliances that contain HCFC-22 (also called R-22) or its blends, including window units, dehumidifiers, central air conditioners, air-to-air heat pumps, ground-source heat pumps, and ductless air conditioners. This refrigerant has been the refrigerant of choice for residential heat pump and air conditioning systems for over four decades.

Consumers won't be required to stop using HCFC-22
Consumers won't be required to replace existing equipment.
Existing (pre-2010) equipment using R-22 can continue to be serviced with R-22.
After 2010, supplies of R-22 will be more limited (more expensive?, I think so).
After 2010, only stockpiled or reclaimed R-22 will be available unitil 2020.

The average life expectancy of an air conditioning unit or heat pump is around 15 years. What this means to homeowners, for example, is if you had installed a new R-22 air conditioning system in the year 2002, you will be able to get refrigerant for your system at least until the year 2020 when it will no longer be manufactured. Chances are, within that much time you will need a new system, so you shouldn't base a purchase on Freon alone.