meetup_group_twitter_profiles.rb

require 'open-uri'
require 'json'

# Grab a signed URL from the API console for the group you want: http://www.meetup.com/meetup_api/console/?path=/2/members
url = ''

results = JSON.parse(open(url).read)

results['results'].each do |r|
  if r['other_services'] && r['other_services']['twitter']
    puts "https://twitter.com/#{r['other_services']['twitter']['identifier']}"
  end
end