https://gist.github.com/sasamijp/7628031#file-namechanger-rb-L4

name_changer.rb

 # -*- encoding: utf-8 -*-
require 'rubygems'
require 'tweetstream'
require 'twitter'
require './key.rb'

Twitter.configure do |config|
   config.consumer_key        = Const::CONSUMER_KEY
   config.consumer_secret     = Const::CONSUMER_SECRET
   config.oauth_token            = Const::ACCESS_TOKEN
   config.oauth_token_secret  = Const::ACCESS_TOKEN_SECRET
end
TweetStream.configure do |config|
   config.consumer_key        = Const::CONSUMER_KEY
   config.consumer_secret     = Const::CONSUMER_SECRET
   config.oauth_token            = Const::ACCESS_TOKEN
   config.oauth_token_secret  = Const::ACCESS_TOKEN_SECRET
   config.auth_method            = :oauth
end
#Twitter.update_profile(:name => "test")
client = TweetStream::Client.new
client.userstream do |status|
  if status.text.include?("(@uh700)") && !status.text.include?("RT") then
    text = status.text.sub("(@uh700)","")
    text = text.sub("@","")
    Twitter.update_profile(:name => "#{text}")
    option = {"in_reply_to_status_id"=>status.id.to_s}
    tweet = "@#{status.user.screen_name} #名前が{text}になりました"
    Twitter.update tweet,option
  end
end