Try the Jacquies Torres place in Brooklyn. It's much nicer and friendlier.
Chocolate Bar is nice but totally overpriced. Same as Marie Belle. I think also that Jacques Torres supplies both places with the chocolates.
If you're new to the city and eager to try Chocolates, you should go to the New York Chocolate Show in November in Chelsea.
It will satisfy your chocolate fix and then some.
The Ritz Carlton down in Battery Park offers a similar AYCE chocolate buffet but only for one month out of the year (I think it's February, but you should double-check). It ain't cheap.
Also note that there is a chocolate demo show once a year usually in the Puck Bldg. Lots of samples given out, but I find that the earlier years of the show were cheaper, less crowded and with more/better samples given out. Haven't gone in a number of years. (Search for threads on it.)
stjenkins, you seem to spend way too much time with chocolate.
Max Brenner is like a jampacked Cheesecake Factory. Scarily suburban. My chocoholic wife and I fled.
Cluizel in ABC is a much better, more refined, peaceful choice. Jaques Torres can be a bit of a zoo, but has great chocolate.
I don't recall, does Chocolate Bar have any seats??? It's a great place for boxes of chocolate.
Marie Belle on Broome Street in Soho has a storefront and cafe in back with a multitude of hot chocolates and small plates. It is most like the shop in the movie "Chocolat" if you know it. Except there's no Juliette Binoche divining your aura and picking chocolates for you.
Cluizel in the ABC Home store is similar, 19th and Broadway - great staff, cozy, and adventurous choc case. Hot choc here is delish.
These are two of my favorites because of the variety, ingenuity, and service. They are also nice enough for a date.
The touchstone for hot chocolate lovers here is City Bakery, on 18th between 5th and 6th. They have a thick hocho (with or without home-made Marshmallow) . It is really more sweet than you can possibly imagine but also chocolatey. They also have one of the best buffet lunch/brunch in the neighborhood. There is a chocolate "room" - literally a closet on one side of the restaurant which has various single-origin and other specialty chocolate items for retail sale. The pastries and cookies are good. I'm not a fan of the custard tarts - too bland. In early February they celebrate their Hot Chocolate festival, closing off 18th and doing all kinds of block party shenanigans (with free hocho) and then they spend the month concocting specialty hochos (one for each day).
There's also Chocolate Bar (like an overly retro coffee house) in the West Village, on 8th just south of 12th (bright orange and brown).
Vosges in Soho is a Chicago-based co with an emphasis on spiced truffles - especially unusual spices, like pandan. They have bars too and nice packaging. You can also get 3 kinds of chocolate chaud - Parisian, White Lavender (surprisingly good) and Mexican (cayenne-spiced.) Also ice cream. Few seats and Spring St crowds, but the staff are friendly and the chocolates are good. (Spring and...Wooster?).
Jacques Torres over on Hudson street is neat with the workings of the chocolate maker right there through the big plate glass windows - the cafe itself struck me as a bit Alice-in-Wonderland. Surrounded by bright fabrics and chocolate molded into a thousand different kinds of objects, they have a bar and a retail counter.
In midtown, the Parisian company La Maison du Chocolat has 2 outposts - one in Rockefeller center on 48th (next to NBC Studios) and one around 70th and Madison. The latter has more seating. Atmosphere is a bit prim.
There are others, including plenty with no seating, just "takeout". Haven't tried Max Bremmer yet - most of the posts seem down on it. I looked inside one Friday evening after a movie and thought it was what Hershey's factory would look like if it was in Blade Runner.