Adobe has announced that all future development will be cloud-focused. They have also said that for those who want to stay with a perpetual license model they will continue to make CS6 available though resellers and the Adobe store "indefinitely," but that there will be no new features added to CS6.
Essentially, this means you have the option of freezing your applications at CS6 or, if you want to continue to move forward with new fetures as they are developed, you can subscribe to the Creative Cloud. Cloud subscribers will be able to download and install CS6 (as well as future "old" versions) to facilitate collaboration.