I have a beta key (they can be gotten for free). I played much of the weekend.
Neverwinter Online (NWO) is an Action RPG MMO. NWO is Diablo or Torchlight, but with a third person camera. NWO is not a translation of DnD rules of any edition into MMO format, it uses a traditional action rpg style ruleset, with DnD names assigned to things.
If you do not like action rpgs, you will not like NWO. You can safely ignore any and all dialog and story. If you like RPGs, I would in fact encourage you to actively do so, as your head may explode otherwise.
The game is slated for release "early 2013", and official video streams from Perfect World (PW is the owner of Cryptic, the dev making NWO) mention April. The game as it stands in this second beta has numerous serious bugs and other basic multiplayer and party issues. I do not believe all the issues and bugs can be addressed before the end of April (the latest possible date that fits their current release announcements).
Neverwinter Online will be free to play. Cryptic plans on making money via microtransactions, selling game currency, armor dyes, unique mounts etc. During beta, it did not appear that anyone would need to buy anything before coming to a conclusion on whether they like they game or not.