“Simply put, Ubuntu cannot compete with Red Hat server-side: Red Hat is simply too well established and no one is going to deploy Ubuntu Server, over RHEL, and keep their job at the same time.”
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Canonical Ltd. are the official sponsors of Ubuntu Linux, with Mark Shuttleworth providing the funding, via Canonical, to move Ubuntu forward. So far, about $15-20 million has been spent.
And even at this point in time, with the top Linux distribution, the future is very uncertain. Mr. Shuttleworth has stated himself that it might take another two years before he even knows whether Canonical/Ubuntu has a chance to become profitable.