QuoteShuttleworth described desktop adoption of Unity as the "most significant change ever" for Ubuntu. He also acknowledged that it is a "risky step" and that much work remains to be done to prepare for the transition. The move reflects Ubuntu's growing divergence from the standard upstream GNOME configuration and effort to differentiate itself with a distinctive user experience. During the keynote, Shuttleworth emphasized that Ubuntu is still committed to GNOME despite the fact that it will ship with Unity instead of GNOME Shell. He contends that diversity and competition between different kinds of GNOME environments will encourage innovation and benefit the GNOME ecosystem.
The decision to ship a custom interface in Ubuntu is going to be controversial. Critics in the upstream community are already expressing disappointment with what they view as a move to fork the desktop. It's worth noting, however, that Canonical isn't the first company to build a unique user experience for GNOME that deviates from the standard upstream user interface stack. Intel also similarly produced a custom shell with the Clutter that is used on the MeeGo platform. Canonical's deviations from the upstream configuration receive closer scrutiny because Ubuntu's popularity among Linux users makes the distribution a king-maker on the Linux desktop. Canonical's decision to ship Unity could deeply marginalize GNOME Shell.