Social+Media+Defined

As you can see, those different tools and services can be grouped into categories:
 * **Publication tools** with blogs ([|Typepad], [|Blogger]…), wikis ([|Wikipedia], [|Wikia], [|Wetpaint]…) and citizen journalism portals ([|Digg], [|Newsvine]…)
 * **Sharing tools** for videos ([|YouTube]…), pictures ([|FlickR]…), links ([|del.icio.us], [|Ma.gnolia]…), music ([|Last.fm], [|iLike]…), slideshows ([|Slideshare]), products reviews ([|Crowdstorm], [|Stylehive]…) or products feedbacks ([|Feedback 2.0], [|GetSatisfaction]…)
 * **Discussions tools** like forums ([|PHPbb], [|vBulletin], [|Phorum]…), video forums ([|Seesmic]), instant messaging ([|Yahoo! Messenger], [|Windows Live Messenger], [|Meebo]…) and VoIP ([|Skype], [|Google Talk]…)
 * **Social networks** ([|Facebook], [|MySpace], [|Bebo], [|Hi5], [|Orkut]…), niche social networks ([|LinkedIn], [|Boompa]…) and tools for creating social networks ([|Ning])
 * **Micropublication** tools ([|Twitter], [|Pownce], [|Jaiku], [|Plurk], [|Adocu]…) and alike ([|twitxr], [|tweetpeek])
 * **Social aggregation** tools like lifestream ([|FriendFeed], [|Socializr], [|Socialthing!], [|lifestrea.ms], [|Profilactic]…)
 * Platforms for **livecast** hosting ([|Justin.tv], [|BlogTV], [|Yahoo! Live], [|UStream]…) and there mobile equivalent ([|Qik], [|Flixwagon], [|Kyte], [|LiveCastr]…)
 * **Virtual worlds** ([|Second Life], [|Entropia Universe], [|There]…), **3D chats** ([|Habbo], [|IMVU]…) and teens dedicated virtual universes ([|Stardoll], [|Club Penguin]…)
 * **Social gaming platforms** ([|ImInLikeWithYou], [|Doof]…), **casual gaming portals** ([|Pogo], [|Cafe], [|Kongregate]…) and social networks enabeled games ([|Three Rings], [|SGN])
 * **MMO** ([|Neopets], [|Gaia Online], [|Kart Rider], [|Drift City], [|Maple Story]) and **MMORPG** ([|World of Warcraft], [|Age of Conan]…)

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