It is fair to say that social media is rapidly becoming a
necessary tool in any organisation's marketing toolkit. However,
for any business to justify its time spent on social networking, it
really needs to understand the true opportunity that particular
social media audiences represent. For example, if you are a
business local to Brighton, it would really help if you knew how
many Twitter or Facebook users were in your geographic locale so
you could make a more informed choice of social media service to
promote yourself in.
We thought this was worth investigating, so armed with Microsoft
Excel and data sets available online we came up with a league table
of towns in the UK with highest densities of Twitter users.
Interestingly, although London had the highest number of Tweeple,
it was actually 10th in the list when population density was
factored in, out-performed by many of the UK's media cities
including Manchester, Liverpool, Glasgow and Bristol. We have
summarised the full results in the figure below (click upon the
image for a full-size version):

Circles represent number of people signed up to Twitter with a
particular location set per head of population. Twitter user
numbers from Twellowhood (opens new
window) with some amalgamation of numbers where multiple
spellings of the same place name had significant numbers of
users. Population figures from Wikipedia (opens new window).