The answer is:
No.
Other than the Windows Ubuntu One situation, as of right now there is no reason any questions about say, Unity on Arch would be on-topic, or Ubuntu Software Center on Solaris (How they got that working is beyond me!) or Mint, or straight Debian, or some other Linux distro.
Related: Are Linux Mint (and other unofficial derivatives of Ubuntu) questions on topic?Are Linux Mint (and other unofficial derivatives of Ubuntu) questions on topic?
