Landscape is a commercial service that Canonical provides to customers. Like all our services it's an optional piece that an Ubuntu user can choose to use if they have the need. The core Ubuntu platform is completely gratis and open source - in fact we'll even send you an Ubuntu CD anywhere in the world so you can try it out!
The client side of Landscape (the piece that sits on a users desktop or server) is open source. It's provided within Ubuntu server and is easily installed on the desktop edition.
The server side of the service is closed source and the whole thing is provided as a web service by Canonical. All the code for Landscape (client and server) was developed by Canonical developers. Of course we used free software components such as Python and Apache. We've also open sourced or support a few components that Canonical developed internally/uses for Landscape such as Storm and the SMART package manager.
You can find out more about Landscape or register for a trial on Canonical's <a href=http://http://www.canonical.com/projects/landscape>Landscape</a> pages.