In an interview at Gamasutra, Cryptic CEO Jack Emmert admitted that the game doesn't have a business model nailed down yet, and that all options are still on the table, from a "free-to-play with microtransactions" model to a "pay-by-the-minute" one. Emmert makes the point that asking for a subscription is still a viable way to run an MMO -- he fully expects BioWare to charge subscriptions for The Old Republic -- but that requires meeting a very high standard in terms of its content and quality.
Of course, Neverwinter is described more as a "co-op experience" than an MMO, and Emmert says it is indicative of a "new direction for Cryptic." Instead of worrying about MMO standards and traditions, he says, Cryptic wants to "just make great games." Specifically, that means "no more 75 Metacritic scores," he jokes at the end of the interview. "My heart just can't take it anymore."