The problem, of course, is that by combining proprietary software with Linux, you're also legitimatizing the use of proprietary programs with open-source.
...and, IMO, it's a very big problem, indeed. Goes to the root of the GPL III controversy. The more I think about it, the more I tend to support Stallman's position over Torvald's. Hopefully, there will always be distro's like Debian that emphasize the importance of FOSS, and insist that non-free elements of GNU-Linux be identified as such.