According to the January 2006 release of a Samsung and POPAI digital survey, there are close to 100,000 digital signs installed in the United Kingdom. The purpose of the survey is to establish the number of digital screens in stores across the UK.
UK's population is about 60 million resulting in a ratio of 1 screen for every 600 people.
Read the study here: In-store screens increase by 63 percent (PDF File)
We wonder how many screens are in the United States.. If you know of any studies, please post a comment.