RED HAT wanted to remove Mono from Fedora and it finally went ahead and did it. The Microsoft vs. TomTom case raised awareness and led to greater opposition to Mono, but there are other factors at play (some of which not related to patents, either). Only such rational opposition to Mono prevents GNOME Zeitgeist from stepping on a trap. To quote from a new blog post:

Before UDS, GNOME Zeitgeist was getting some good attention, but sadly we never got directions from anybody concerning the engine. All of the Developers are actually students so our time and resources are limited. This however all changed during UDS. Thanks to David Barth and Emmet Hikory who took the time to sit down with us to understand Zeitgeist, thus setting new directions for the Zeitgeist “Service” as well as a strategy to avoid any political problems (sorry guys I am a Mono fan boy, but sadly the 2 other maintainers in the Team aren’t, so no worries the only language the engine would be ported to would be C). And for the first time we have a semi roadmap, thanks to the UNR team Milo, which we never got to set up since we were busy developing and going with the flow.

Even OpenSUSE recognises drawbacks of Mono

Mention Mono in a story and you are certain to draw two kinds of readers - the followers, those who have drunk the kool-aid ladled out by Novell vice-president Miguel de Icaza, and the detractors, who realise that it could cause them patent headaches a few years hence.

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Easy-LTSP was originally written in C# but, according to the OpenSUSE project "Easy-LTSP was designed to work on any distribution, but unfortunately it is not integrated anywhere other than openSUSE, discussing with the upstream LTSP developers suggested the slight reservation could be due to it being written in C#."

Easy-LTSP is being rewritten to include new features and OpenSUSE has now decided to use Python instead, "which would be easier to attract more contributors and increase possibility that users of all distributions running LTSP server can benefit from it inclusion in their preferred distro."