Here is the direct link to download the poster from the official homepage:
http://rm.coe.int/CoERMPublicCommonSearchServices/DisplayDCTMContent?documentId=090000168058cf6a
In case they take it down someday, here is the archived link in the Wayback Machine:
Wayback Machine
Sometimes truth...
If anyone else wants an official source of the poster, what about this:
Go to this official homepage:
Finding posters / Trouver les affiches
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Europa : viele Sprachen, eine Stimme
Gets you the poster in German. Is this more or less sinister than the English version? I...