1. What you look like. Julian Niccolini, the famed maitre d' at the Four Seasons in New York City, says he regularly uses Google Images to identify new guests, which allows him and his staff to greet diners personally when they arrive.
2. How many times you've stood them up. Ann Shepherd of OpenTable, which handles online reservations for more than 15,000 restaurants, says the site does track data on diners who have a habit of blowing off their reservations. "If a diner has a certain number of accumulated 'no shows' their account is closed," she says. The system also notes—and prevents—a customer from double-booking at two different restaurants.
3. What you ate the day before. New York City's Eleven Madison Park recently served a customer a mini lamb burger after he tweeted, "Burger King in the airport waiting for my flight to NYC. I'll consider this my amuse-bouche for Eleven Madison Park!"
5. Whether you're cheating on your wife (or husband). Let's say you are a regular at a restaurant—and you regularly alternate between dinner with the spouse and dinner with, well, someone who is not your spouse. The great maitre d's discreetly take notice. "As part of our pre-shift meeting, we review the [reservation] books with the staff," says Welch. "And where there's a situation where a guest comes in with somebody new, it's 'Lovely to see you again.' It's not about what happened yesterday and who the individual was with then. We're not here to judge."
The internet provides a wealth of information about your guests, some is relevant, some is not and like mining it require some effort to extract.
