Blues Alley Japan. is a sophisticated club with great food and an eclectic live schedule. It's basically what the Blue Note is trying to be but isn't; a fancy place to take some customers, but where the business crowd does not overwhelm the music.
The website has a useful guide on their live calendar letting you know exactly what genre is being featured that night, anything from straight-ahead jazz to World or even lite-soul. Lots of good pictures of the interior on their site too. Reservations are recommended, and bring your credit card..