Opened for business today. It aims to be a one-stop shop for accommodation, travel, foreign exchange, phone rental, trip bookings, car rental, luggage forwarding, interpreter services and restaurant reservations. It's run by JTB with help from the Tokyo Chamber of Commerce. The word "premium" makes me think that you'll pay more than if you arranged everything yourself but I haven't checked any prices.
You submit your requests to the site and pick up all the appropriate coupons etc at the counter when you arrive. It doesn't look like you can pay for anything by credit card in advance so any settling up will be done at the counter or with the vendor directly.
Website
EDIT: Actually, it seems many services are charged ahead of time. They quote you a price and you get the confirmation after paying. Not sure how that works for restaurant reservations. Perhaps it means you have to choose your menu in advance which, I suppose, might suit some travellers but seems a bit limiting.