The founder of the company is Daniel James, who was one of the founders of Linux User & Developer magazine, and the original director of the linuxaudio.org consortium. Free Ekanayaka is in charge of software development -- he is a Debian Developer, and is best known for his work on the AGNULA/Demudi Linux distribution.
Linuxaudio.org is a not-for-profit consortium of libre software projects and artists, companies, institutions, organizations, and hardware vendors using Linux kernel-based systems and allied libre software for audio-related work, with an emphasis on professional tools for the music, production, recording, and broadcast industries. 64 Studio is a member of the linuxaudio.org consortium.
Due to the architecture-agnostic nature of most Linux and Debian code, nearly all the software we are using can be compiled natively for 64-bit platforms. So it's as good as any Linux distribution can be, only built to make the most out of today's hardware. You'll have to decide for yourself if it can replace Windows or OS X -- but what its developers say is that a default install of 64 Studio will provide far more creative tools than either of those platforms, and will also be considerably better value.