Leonardo wrote:so what is the difference between cs1, cs2, and cs3?

in theory, adobe has cs32 ready for global deployment. you just won't see it until 2039. it's one thing if an upgrade is vastly improved from one version to the next, but adding a few new filters and export options is pure obsolescence.
here's a definition from wikipedia.
Planned obsolescence (also built-in obsolescence (UK)) is the decision on the part of a manufacturer to produce a consumer product that will become obsolete and/or non-functional in a defined time frame. Planned obsolescence has potential benefits for a producer in that it means a consumer cannot just buy a product once and never have to buy again - the life of the product's usefulness or functionality is fixed, so that at some point the consumer must purchase again, whether returning to the original manufacturer for a newer model, or buying from the competition. For an industry, it stimulates demand in the marketplace by ensuring a customer must come back into a buying mode sooner than had the product been built to last longer or indefinitely. It exists in many different products from vehicles to lightbulbs, from buildings to software. There is, however, the potential backlash of consumers that become aware of such obsolescence; such consumers can shed their loyalty and buy from a company that caters to their desire for a more durable product.
Planned obsolescence was first developed in the 1920s and 1930s when mass production had opened every minute aspect of the production process to exacting analysis.
Estimates of planned obsolescence can influence a company's decisions about product engineering.
Therefore the company can use the least expensive components that satisfy product lifetime projections. Such decisions are part of a broader discipline known as value engineering.