Munich is not enough. We have the same kind of example here in Finland - the city of Turku. It was nationwide reported that Turku is seriously going open-source. IBM made a study for Turku (objective or subjective, guess?) - you can download the report here (in finnish) IBM_Turku_selvitys.doc (415.5 KB). Conclusion of studies were that 60% of the departments in Turku were for IBM/Linux and 40% Microsoft. These figures were based on nothing as it turned out, read here. After 2 1/2 years of investigation they still do not know what to do and the majority is against IBM/Linux, read here.
You can also download the report made by Turku IT department - in finnish: Turku_linux.doc (177.5 KB) or in english: selvitys14082003.pdf (326.97 KB) - where the users are more for Microsoft Office, but the conclusion of the report is for Linux and OpenOffice.
My opinion is that Linux advocates hurt more themselves by not proving their claims. Discrediting others does not prove anything. Be open - as open-source - and tell honestly about positive and negative issues in Linux, get studies to support the claims.
I for one (as a Windows user) admit that Linux is a damn good server product, for that I give it credit. But on desktop - never in a million years. More usability, more user studies, include all the existing features that Windows has now and Linux might succeed. But it will take time.
Btw. Paris is trying to do the same mistake (read here) or just blackmailing Microsoft.