I wonder if your characterisation of Gentoo as being a non-commercial distribution is valid. I notice that they sell CDs and ask for donations on their site, which seems to make them just as commercial as Mandrake Linux (which offers Club Memberships to support development and sells more complete products on their site).
Many people are not aware that Mandrake Linux is almost as community-oriented as Debian. Major packages in the main distribution are maintained by community contributors, all packaging and software sources are available in public CVS, community members have commit access on a lot of Mandrake-specific software and the development wiki (http://qa.mandrakesoft.com) and full rights in bugzilla. About the only aspect that community members don't have full access to at present is the aesthetics (logos, default desktop settings etc).
I am not that familiar with Gentoo development, but I don't think it is as open as this ...
So, is "commercial" the correct distinction to make, or is community involvment?