Upload & Sell: Off
CS6 could be around for a long time. Third party developers can keep it current with new features as addons. This as long as we don't see operating systems and hardware going to 128-bit processing or something that would make it not run in new machines.
How do you know Adobe won't turn off CS6 authentication servers? Or make the process of using your legally acquired software impossible?
When the cost of fighting CS6 users via class action in court becomes manageable, Adobe will just chalk users legal action up as an operating expense. My guess is they have already budgeted for this and their lawyers are ready.
Apple upgrades its OS every year with no incentive to keep a competitors product viable, imho, so there is a potential CS6 will be deprecated as early as this fall.