My thoughts are this is rubbish.
With a combination of the credit crunch and the appalling weather this year the main concern of the contractor is staying in business.
It is estimated that the small split market has collapsed by up to 60% from the 2007 figures. The end users is not remotely interested in replacement either, they are tightening their belts and trying to reduce spending as well.
My prediction is that the old R22 kit will march on for years to come and will slowly be replaced as it fails or leaks.
From experience, I've found, if the old gear runs for 5 years it generally marches on and on.
Leaks do not just spring up. It must have been well installed, if its been running for years. Only accidents cause problems.
The main cause of death for this old gear is availability of parts NOT refrigerant. Manufacturers rarely keep parts after 10 years so when anything fails you have no choice but to replace it.
Recently I went to a site and a saw a load of old VRF kit which had been in since 1994. Its all perfect. Marching on like it was new. Something you have to consider is that kit in the early 90s cost twice what it does now and was more ruggedly built.
I think we will still have ancient R22 kit running on for years to come fault free. We will see and if I'm wrong, no problem. Most contractors are begging for work so they will take up the work as it comes in.