Some of these accusations might be dismissed as the jealousy of those who have not been hired. Moreover, while free software licenses permit -- even encourage -- code borrowing, you can easily imagine Debian members being upset to see Ubuntu becoming successful while their own efforts go unrecognized. As Kevin Bowling describes the situation, "Ubuntu is stable because they are standing on the shoulders of giants," perhaps without mentioning the fact as often as it might.
Yet the largest reason for complaints from the Debian distribution seems to be a difference in culture. Where Debian is democratic to a fault, Ubuntu is ultimately led by Mark Shuttleworth, who half-jokingly describes himself as dictator for life. Just as seriously, while Debian prides itself on non-commercialism, Ubuntu's goal is commercial success.
Consequently, when Shuttleworth offered to help Debian meet a proposed feature freeze, the offer was seen in some quarters as less a generous offer than an attempt to control and manipulate Debian -- especially when the decision to meet the freeze was not debated and voted upon in Debian's usual fashion.
A similar, more general resentment also exists in the free software community in general. For instance, while acknowledging Ubuntu's many improvements in usability, Blackbelt Jones accuses it "of a lack of empathy for me, the experienced Linux user. In re-engineering Debian, Ubuntu creates detours in the familiar highway of GNU/Linux administration, and then doesn't bother to put up a sign. And so, before I know it, I'm off the road."
Jones cites the simple example of labeling Ubuntu's KDE packages "Kubuntu desktop," which emphasizes Ubuntu's sub-distro while confounding the expectations of experts searching for KDE. But other examples abound, such as adding changes to notifications in GNOME before they are accepted by GNOME and replacing the init daemon with the appropriately named Upstart.
Others complain that the new users who are attracted to Ubuntu know nothing about Linux in general. "They seem to think Ubuntu is responsible for all that is good in the [free software] world," Bowling complains. As often as not, changes that are credited to Ubuntu would be more properly credited to the GNOME desktop or another piece of software, and alleged innovations by Ubuntu can also be found in distributions like Fedora or openSUSE.
However, a far more serious charge is that Ubuntu manipulates the free software ethos for its own advantage, making changes within its distribution rather than in specific projects where others can easily share them.
This charge has been whispered off and on for years. But it found its strongest form in the keynote delivered by kernel developer Greg Kroah-Hartman at the 2008 Linux Plumber's Conference. Throughout his presentation, Kroah-Hartman used Ubuntu and Canonical as a example of an organization that was not contributing to the community as it should.
According to Kroah-Hartman, Ubuntu contributed only 100 of 99,324 kernel patches in the last three years -- substantially below the 11,846 from Red Hat or the 7,222 from Novell. He also found similar statistics in contributions to GCC, X.Org, ALSA, and other core aspects of GNU/Linux. His conclusion? "Canonical does not contribute to Linux plumbing."
Further, Kroah-Hartman stated flatly, "Developers who are not allowed to contribute to Linux should change jobs," in effect urging Canonical developers to quit -- a plea that seems to have been almost entirely ignored.
Like other complaints from the community, Kroah-Hartman's keynote can be seen as partly personal -- the fact that he is employed by Novell could indicate that he is attacking a rival of his employer. But, at the same time, the trend he indicates is too obvious to ignore. The numbers are not even close.