Chowhounds of New York:
I moved to Manhattan five years ago from a small town in Connecticut, and was immediately overwhelmed. Instead of five sushi restaurants in town, there were five sushi restaurants on my block. Fortunately I discovered Chowhound, and for five years I've gotten amazing Manhattan tips until I feel like I can eat my way around the island. I'm moving to the left coast, so I wanted to thank all the contributors here, and as a final thank you, here's a list of my personal answers to perennial chowhound questions:
Best Black and White Cookie? Rocco's on Bleecker Street, hands down. They also have excellent cannoli, filled to order. Their B&W cookies aren't dry for you traditionalists, but they taste better.
Pizza in Manhattan? Probably Arturo's on Houston, but if you can't make it there find a Patsy's, which is pretty reliably decent. They also have this amazing fried zucchini and eggplant appetizer with garlic dipping sauce which is worth it, usually.
First Date/Parents are in Town/Not too fancy/not too casual? Five Points on Great Jones Street.
Is Babbo worth it? Yes, but please get the beef cheek ravioli. Beef cheeks aren't scary, really.
Bargain Meal? There are a million and one places to get fantastic and super cheap food in the city, but for more of a nice dinner experience you can't beat the value of the Tavern Room at Gramercy Tavern. Of course, you'll have to wait, but the bartenders are nice, the drinks creative, and the bar nuts to die for.
Old New York Experience? Hands down the Bemelmans Bar in the Carlyle Hotel on the UES. $20 cover after 9:30, but at 9 they play bad elevator music -- go earlier to listen to the jazz piano without paying the cover. Runner up is an oyster pan roast at the Grand Central Oyster Bar.
Food Shopping? For one stop shopping, Grand Central Market has a pretty good butcher, a great fishmonger (Wild Edibles), a decent produce selection, great cheeses (Murray's) and a good bakery (Corrado). It's pricey, but very convenient and good quality. Also recommended is Chelsea Market (explore Buon Italia for some great Italian import finds), or Bleecker Street for the original Murray's. And the Saturday market at Union Square.
Cupcakes? They all taste pretty much the same (very sweet), so you might as well milk the nostalgia factor for all it's worth and just go to Magnolia. Billy's in Chelsea isn't bad.
But where do you get a birthday cake? Black Hound in the East Village, or the Sour Cream Chocolate cake from Buttercup Bake Shop.
I'm sure there will be a million people who agree with some choices but not others, and a million people who agree with all of them, and a million people who think I've mislaid my tastebuds somewhere. I will miss New York, and the NY Hounds have added immeasurably to my experience of the city.