My first thought was "Wow! That's a risky move by Adobe." But the more I thought about it, I realized they can get away with only offering a subscription-based model. Their userbase is huge, and pros won't have a problem with the cost because they likely spend it already. I can't think of another company who could pull such a drastic move and not end badly for them.
I believe this model is a little cheaper for one who uses the suite every day, and upgrades when the next version comes out. But for someone like me who only uses the suite a few times a month, and doesn't upgrade every time, it's a tough pill to swallow. Ignoring the introductory rate for the first year, the yearly cost is $600USD.
Luckily, my last upgrade was CS5, and works well for me now and into the foreseeable future. But there will come a time where I'll need to upgrade. I'm not sure how long they'll continue to offer CS6 as a purchasable product, and even at that point, it may not be worth the money. I may have to explore other options, which is disappointing.
You can rent their software on a monthly basis, it just costs more. For example, renting Photoshop for a month will cost $30USD. Renting the entire suite costs $75USD/month.