Whats the relationship between rebuilds and Red Hat?
There is no official relationship, but it is a complementary one for which Red Hat has publicly expressed its support, since many of the users using such rebuilds become Red Hat customers when they move into production deployments requiring commercial backing and support. Red Hat has gone out of its way to make it easier for rebuilds by isolating the Red Hat branding to a couple of specific packages and providing all the source RPM packages in a public location.