Only the first occurrence of "created_at" is held as a date. Additionally :user now points to a user object, not a hash.

gistfile1.txt

[27] pry(main)> tweet.to_hash
=> {:created_at=>2013-03-08 13:40:22 -0600,
 :id=>310112778675425281,
 :id_str=>"310112778675425281",
 :text=>"post a twitter.",
 :source=>"web",
 :truncated=>false,
 :in_reply_to_status_id=>nil,
 :in_reply_to_status_id_str=>nil,
 :in_reply_to_user_id=>nil,
 :in_reply_to_user_id_str=>nil,
 :in_reply_to_screen_name=>nil,
 :user=>
  #<Twitter::User:0x007f8b1b4ab610
   @attrs=
    {:id=>1155825132,
     :id_str=>"1155825132",
     :name=>"Not David Zmick",
     :screen_name=>"NotZmick",
     :location=>"",
     :url=>nil,
     :description=>nil,
     :protected=>false,
     :followers_count=>2,
     :friends_count=>2,
     :listed_count=>0,
     :created_at=>"Thu Feb 07 03:05:53 +0000 2013",
     :favourites_count=>0,
     :utc_offset=>nil,
     :time_zone=>nil,
     :geo_enabled=>false,
     :verified=>false,
     :statuses_count=>41,
     :lang=>"en",
     :contributors_enabled=>false,
     :is_translator=>false,
     :profile_background_color=>"C0DEED",
     :profile_background_image_url=>
      "http://a0.twimg.com/images/themes/theme1/bg.png",
     :profile_background_image_url_https=>
      "https://si0.twimg.com/images/themes/theme1/bg.png",
     :profile_background_tile=>false,
     :profile_image_url=>
      "http://a0.twimg.com/sticky/default_profile_images/default_profile_0_normal.png",
     :profile_image_url_https=>
      "https://si0.twimg.com/sticky/default_profile_images/default_profile_0_normal.png",
     :profile_link_color=>"0084B4",
     :profile_sidebar_border_color=>"C0DEED",