Advantage and Disadvantages

Computer mediated communication is a no longer a new phenomenon therefore I think much of the negative effect/stigma has been removed or has simply disappeared (i.e. that anyone communicating via the Internet is a paedo), the only people who cannot/do not see the usefulness of computer mediated communication are those who have absolutely no experience or understanding of their main uses. 

Social networking sites such as face book were going to be an inevitability of the Internet being made readily available to the masses. It has been argued that social networking via the Internet is an extention to the traditional "public sphere", however when most people think of social networking the envisage annoying cattle-market communities such as face book, where people compete by exploiting their talents, looks or otherwise in order to find a partner, engage in lude sexual activity (all over their keyboards!) or just find a lonely local looking for sex. People often overlook real virtual public sphere's where alternative, minority or other cultural groups perform and practice their beliefs with like-minded individuals, and where members from all over the world can apply to join their virtual space. 

They obviously have pros and cons, here's what I think;

The Advantages - 
It connects minority groups and subcultures who otherwise wouldn't have the physical space/means to practice their beliefs.
It connects people who are otherwise unable to communicate with others in face to face scenarios, or at a specified time (old, disabled, or in other countries).
They do not rely on the space-time continuum, you can communicate asynchronously or synchronously depending on your and others' requirments. 
Virtual space on the Internet is also used in business, i.e. video conferencing.

The Disadvantages - 
They create more apathy, encourages txt spk, laziness; fat people who lack vitamin D because they spend every waking moment on their computer.
They are in most cases (face book) pretty pointless yet utterly addictive for some - facebook users argue that it allows you to stay in contact with old school friends who you rarely catch up with, but in my opinion if you're rarely having contact with these people then surely their not real friends and it's only for the purpose of spectacle that you look at their profile to laugh at what they're up to or what new silly hairstyle they have.
Often reality and virtual worlds collide and cause problems that otherwise wouldn't have been created, i.e. sending e-mails under the impression that they are private, coincidentally meeting someone you met online in the flesh when you are unprepared, people using your uploaded material without your permission, etc etc. 
Social networking can be damaging to certain users - bullying etc is more likely to go on and stay unresolved as users can remain mostly anonymous in the virtual world.
As much as the media disproportionately cover paedophiles operating on the Internet, it does happen, and stupid kids may be in danger of meeting up with the wrong person in the wrong place (very rare but possible).

SOURCE : http://uk.answers.yahoo.com/question/index?qid=20090515091336AA8mIrs

Fellow Youtuber ?

YouTube is a video-sharing website, created by three former PayPal employees in February 2005, on which users can upload, view and share videos.

The company is based in San Bruno, California, and uses Adobe Flash Video and HTML5 technology to display a wide variety of user-generated video content, including movie clips, TV clips, and music videos, as well as amateur content such as video blogging and short original videos. Most of the content on YouTube has been uploaded by individuals, although media corporations including CBS, BBC, VEVO, Hulu, and other organizations offer some of their material via the site, as part of the YouTube partnership program.

Unregistered users may watch videos, and registered users may upload an unlimited number of videos. Videos that are considered to contain potentially offensive content are available only to registered users 18 years old and older.

In November 2006, YouTube, LLC was bought by Google Inc. for US$1.65 billion, and now operates as a subsidiary of Google.

SOURCE : http://en.wikipedia.org/wiki/Youtube

How about Tumblr?

Tumblr is a website and microblogging platform that allows users to post text, images, videos, links, quotes and audio to their tumblelog, a short-form blog. Users can follow other users, or choose to make their tumblelog private. The service emphasizes ease of use. The site ranks as the 10th largest social network with 6.8 million weekly visits. According to comScore, Tumblr scored 13.4 million unique visitors in the U.S. in July, 2011 — up 218% from July, 2010. Tumblr, Inc., the company operating the website, has its headquarters in Midtown Manhattan, New York City.


SOURCE : http://en.wikipedia.org/wiki/Tumblr

Facebook?

IT IS

A social networking service and website launched in February 2004, operated and privately owned by Facebook, Inc. As of July 2011, Facebook has more than 800 million active users. Users must register before using the site, after which they may create a personal profile, add other users as friends, and exchange messages, including automatic notifications when they update their profile. Additionally, users may join common-interest user groups, organized by workplace, school or college, or other characteristics, and categorize their friends into lists such as "People From Work" or "Close Friends". The name of the service stems from the colloquial name for the book given to students at the start of the academic year by some university administrations in the United States to help students get to know each other. Facebook allows any users who declare themselves to be at least 13 years old to become registered users of the site.

Facebook was founded by Mark Zuckerberg with his college roommates and fellow studentsEduardo Saverin, Dustin Moskovitz and Chris Hughes. The Web site's membership was initially limited by the founders to Harvard students, but was expanded to other colleges in the Boston area, the Ivy League, and Stanford University. It gradually added support for students at various other universities before opening to high school students, and eventually to anyone aged 13 and over. However, based on ConsumersReports.org on May 2011, there are 7.5 million children under 13 with accounts, violating the site's terms of service.

A January 2009 Compete.com study ranked Facebook as the most used social networking service by worldwide monthly active users. Entertainment Weekly included the site on its end-of-the-decade "best-of" list, saying, "How on earth did we stalk our exes, remember our co-workers' birthdays, bug our friends, and play a rousing game of Scrabulous before Facebook?"Quantcast estimates Facebook has 138.9 million monthly unique U.S. visitors in May 2011. According to Social Media Today, in April 2010 an estimated 41.6% of the U.S. population had a Facebook account. Nevertheless, Facebook's market growth started to stall in some regions, with the site losing 7 million active users in the United States and Canada in May 2011.

SOURCE : http://en.wikipedia.org/wiki/Facebook