What with Americans' affection for cheeky British imports (Lily Allen, Ali G), it's odd that London-bred noodle shop Wagamama--Japanese for "naughty child"--took so long to hit these shores. At its first U.S. location, in Faneuil Hall, diners are seated without ceremony at communal tables, and chatty, opinionated (!) waiters announce--as they beam your party's entire order to the kitchen via handhelds-there's no telling which dish will arrive first. The sass of the service is matched by the spice of the food, full of scallions, chilies, and the like. Our chicken gyoza and teriyaki steak soba came out fast and flavorful; we were less wowed by dessert-a dry, crumbly fudge cake and a gooey cheesecake--which tasted of serious sitting-around time. The latter should be an easy fix, though, for a place that's built its rep on being fresh.