Having set up their financial models for generating continuously smooth quarterly income through annual subscription (maintenance) payments by their customers, CAD vendors now live in fear of said customers delaying payments. After all, costs must to be cut during this recession.
Some, like Bentley Systems, use the hammer approach. Skip paying, and you owe the accountants in Exton all the missed years' worth of payments when you do renew. Sort of a pay-for-service-and-pay-for-no-service "benefit" to the customer.
PTC today announced a carrot approach, calling it the PTC Gold Loyalty Program. In return for affirming your liege to PTC, you get "special offers on products and services that help you get the most from PTC software:" 3dconnexion, Mentor Graphics, Virtalis, Z Corporation, Objet, and Adobe.