As a side note, I work for a large international company that depends on a suite of software provided by a single vendor. We have been using their software since 1992 (!) and our relationship was great. This software company (which was fairly large as well) was bought by another company and then the accountants took over. So, they switched focus to "maintenance licenses", which is the same as subscriptions (you don't own the software, but you get better support, more features and better development).
For a while it worked, until we looked around and realized that every other company in our industry was being much more productive than we were; looking more closely, we realized that what actually happened was that our "maintenance" contracts basically made it easy for the company to fire their developers with massive and brutal layoffs (well, they outsourced it to ghost operators - answer the phone, issue bugfixes that destroyed more than it fixed), deliver little to no updates, but still realize no loss in revenue, and since everything is proprietary, we were locked in.
This looks very familiar and what is to stop Adobe (and any other software as a service provider) from taking the same route? Innovate to the point where CS6 is "irrelevant" and then just take a holding pattern for a few years. You are trapped, you can't get off the treadmill and Adobe has no incentive to continue to innovate based on your requirements, as they already have your business. If they want more profits, just fire some more people and raise the price; simple mathematics, as Mos Def said "killing fields need blood to graze the cash cow"
Not saying any of this will happen (hope it doesn't, especially layoffs), but their is precedence.