Its a little like an online magazine subscription but not entirely.
Its exactly the same program you paid for... perhaps more current... for $79.
Many who use Animation:Master subscribe every year.
The websubcription supports Hash Inc in their development efforts and helps keep A:M available at a reasonable price for everyone. Before we had to purchase the $299 CD first... then upgrade. Now everyone can get A:M for $79. The websubscription cuts these unscrupulous middlemen and those that take advantage of new users out of the equation entirely.
I've noted more than a few companies are moving to this subscription model.
For instance, after a beta cycle, the just released Celtx Studios v2, online project management suite, expects to go to a $50 per year subscription. I expect other companies will follow suit as this business model represents a considerable savings in development, distribution and support to the company as well as the customer.
Note: I'm not trying to sell you Celtx here. Note: It is very much free.
The part that is following the subscription model is for Celtx Studio for content management and online storage. If you are looking for scriptwriting and storytelling program though... check out Celtx.