The poster is portrait format and shows a city in background, instead of countryside, if you look close. He has now re-released its SVG sources.
The posters were printed from a 3521x4978 TIFF file, which is A1 plus 1mm overlap everywhere at 150dpi, making a 50MB upload after removal of the alpha channel. Flyeralarm has done a great job on print with regard to all of quality, time, price, and service.
UPDATE : We have run out of posters on the fourth (and last) day of LinuxTag. 100 posters it was.