Twitter is usually a very diverse medium, because people chat about everything. Even on the day of the outcry about Jan Moir, the tag cloud over Britain was varied in terms of topics. But not today. As this screenshot from 10am shows, today the micro-blogging platform seems to have been taken over by a hidden force. The UK is only talking about one issue: the appearance of BNP leader Nick Griffin on Question Time.

Trendsmap currently processes about 5m tweets a day using various algorithms to list them by region and time. Stronger trends are represented by larger, darker topics. As another Twitter statistic tool, Trendistic, reports, the issue was "hot" for 22 hours from Thursday 6am until Friday 4am and is now building up again.

There was one Twitter account that remained silent, though. The BNP chairman's statistics show: "Tweets: 1." Obviously Griffin isn't much of a Twitterer.