Small to mid-sized shops who get by with less than a dozen SAs and who don't have WAN volume replication concerns might go this route, but there is too much risk for Fortune 500. It mostly boils-down to 3rd party applications, hardware and drivers. If you're a F500, you probably have proprietary storage of some sort and you probably rely on volume replication across the WAN. You want to hook into that storage from Linux, you need a "certified" platform and that ain't going to be an arbitrary set of Ubuntu packages. Sure it will probably work from Ubuntu, until you get kernel panics under load. Then your in-house Linux "experts" call support for the storage vendor and they ask what distro version and driver you're using. When you say "Gutsy Gibbon recent" they laugh and refuse to support you. At that point, your idea of community support doesn't look quite so hot considering nobody in the community can repro your hardware/driver issue.