Oh, Jesus H. Christ, I could be typing all night about this. Neb, you might as well just shoot me an email.
The boys here are all correct, Williamsburg is fucking sick with restaurants, I know because I live here. I have a friend coming for 4 days on Thursday, and the places here are so damn fantastic, I'm not even going to bother taking her into the city for meals.
BUT, as Neb has pointed out, his friends would like to eat in Manhattan. Seriously, a little help from you as to what their tastes and budget are. Might I point out that if you head to
NY Mag Restaurants, you will notice that they have listed 2,341 restaurants for the city of Manhattan alone. Brooklyn, add another 500. This is actually a fantastic reference for food, what's great is how they have it broken down so tightly by neighborhood, too. I've used this list numerous times to find something new and amazing, and the reviews never let me down.
I eat in so many damn restaurants, and it runs the gamut from hipster burger places (The Lodge

) to taking out business associates to Tao. So let us know what kind of restaurant experience they are looking for, or if they just want to know where to avoid if they happen to be in Times Square.
I have to agree with ilia on Tomoe, that place gets complete raves from every single person I know. Nobody argues that it isn't one of the best sushi places around. And you won't be paying Nobu prices.
I love all of Mario Batali's places (he's got 9 here), Otto is a great pizza style joint, The Spotted Pig has been name dropped more times than I can count (everyone loves to tell which celebrity(s) they saw there. Bono!) So his restaurants alone could take up all meals.
Another surefire restauratuer to follow is
Jean-Georges. Mercer Kitchen, Perry St., Spice Market, I love all of them.
Seriously, what am I doing, just send me an email.
Nick