This is a game that interested me and I'm a cheap bastard so it fits the bill(free). I also enjoy STO, so if they model the game along those lines I can see this being good(as in, a F2P game that doesn't ruin the actual game if you don't buy anything).
So, is it any good? Just a quick and dirty synopsis or something. Is the combat like every other ground based MMO? I could put up with STO space combat, because it's space and I'm flying around in Star Trek shit. Do parties actually do party-based stuff, as in, are the quests complex at all? I've got some people I could play through with if I convinced them, but not going to download if it's same old stuff. Does any part of it actually feel like playing AD&D on the computer?
Well depends a lot on how you interpret AD&D. Me, I think it captures the feel of how I'd picture high-level d20 to be like, very over-the-top, comic book like action. The key thing is that Neverwinter does not directly use any d20 mechanics, but rather uses an action game-like system refined from Champions and STO.
I'd say it's a very good game overall, having a good fast-paced action core with a character system that makes a difference and that emphasises quality over quantity. You have fewer abilities than norm for MMOs, but all of those abilities are very important, and on top of which each class comes with certain unique mechanics (ie, the Cleric has a fighting game style second power bar used to cast "EX" versions of their spells, the two Fighter classes don't get a dodge roll but instead either Sprint or Guard with a shield, etc). Also of note is that so far power creep has been tame, due to the steep diminishing returns for higher stats from equipment in the game (IIRC the jump from old Ancient equipment to Fomorian equipment was 1-3% increase in DPS). As for party-based content, I'll be the first to say that I wish there was more party-based content that wasn't about wading through a dungeon of varying degrees of difficulty encounters (if there's one thing you can say for NW, it's that its endgame content is more than happy to rape you in the ass if you fuck up), so it's largely just party composition and battle coordination tactics instead of stuff I'd find more interesting like puzzles making use of the different classes' abilities and the like. Then again, the Foundry hits that spot, given how flexible it is for an MMO UGC toolset (Foundry can support very complex mazes, architecture and scenarios, even if it has to adhere to linearity).
Regarding the paying end of stuff, currently Neverwinter has a pretty good state of things. There's not really anything genuinely useful outside of higher rank mounts and character slots (character slots are the big thing, since each will increase your income flow and lottery chances by 100% over just one slot) that's paywalled, most of it gravitates toward vanity stuff (and the choice between Cat and Ioun Stone companion is largely down to preference once you get some cashflow set up).
So really, give it a shot and see what you think.