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The algorithm works roughly as follows:
 - do some string matching
 - weight according to how many articles the stream for that tag will contain
 - pick the first section, region, person, organisation and topic matching, in that order
 - show more topics, regions etc until reach 150 characters 

TODO: change ft-poller to be able to do POST requests, then poll for metatags from within the app

![image](https://cloud.githubusercontent.com/assets/447559/5142310/fdb7325c-7178-11e4-8075-63cb31cb787a.png)