It is sad to have to say this, but color management as required by graphic arts applications is very poorly implemented under Linux. There is no universally agreed-upon CMM(color management module), and applications do not uniformly implement and respect color management. Also, creating and maintaining ICC profiles under Linux is a difficult proposition at best. The best profile generation package, Argyll, is an open source command line product that is unable to work directly with scanning tables like the i1io, Barbieri, or Colorpartner units. Argyll's UI approach is not anywhere as convenient as products like profilemaker, monacoprofiler, or i1profiler. For those who need to use a RIP, there is exactly one offering available- Caldera.
I wish Linux could support graphic arts and printing for professional printers as well as Win and OS/X.