According to a new post on the Darkfall: Unholy Wars site, Aventurine is exploring a pair of revenue models in exchange for the currently in place subscription model. The post begins with a discussion of the principle differences between a freemium and a free to play revenue structure.
The discussion winds down to two main points in the "freemium" model as the preferred method of revenue generation: F2P requires continuous development of shop items and that a large portion of the game mechanics are affected by these same items.
While not yet fully decided, Aventurine has indicated that a free trial, already partially implemented in the game, may be made more robust, though it will require some back end work to allow for the creation of trial accounts.
Want to weigh in on the topic? Head to the Darkfall: Unholy Wars forum.