What are the pros and cons of social networking site such as facebook and myspace?

[megan.jones_march1990]

[voicelesseggnog796]

Pros: tons of mates and relatives to chat with

cons: there's bad people too

[Darius]

Pros: Zero

Cons: Lots of them

[CoeurDeLion]

Referring to Facebook, as it's really the benchmark:

Pro:
It brings together people from all walks of life, in one site. One log in lets you manage contacts from every part of your life: work, school, private life, family.
You get updates on your loved ones
You can get reunited with old friends from school, family members you never knew existed, and even people you thought were dead!
It's used almost worldwide, so you can find friends internationally.
It enables companies to target people with very well chosen advertising, that really and genuinely interests the person to whom it is sent, because it's based on their social activity.

Cons:
A security breach, or hacking of an account may make identity theft possible. Not only that, but the hacker could have access to details of all the hacked person's family, and info such as cellphone numbers or addresses may be lost like this.
Some of the apps have to be paid for, and if and when these applications, games etc fail or the internet is down, effectively the money will have been spent on nothing, as with unrewarded gambling.
There's an increasing consensus that the internet is addictive, and many people find that facebook is controlling their lives to an unacceptable degree- people also waste a lot of time during working hours logged into facebook, and have been known to share privileged customer information with the public via their facebook page- company data protection has also been breached like this.
Many recruiters check out the facebook profile of prospective employees- and some companies can search the entire Facebook history of a profile, finding pictures of the candidate drunk, misbehaving or even indulging in illegal activity- such as with the Vancouver riots, when many people boasting about their vandalism were shopped by their friends.
What's put on the internet is out there forever- some people rant against friends and even loved ones on Facebook, and don't realise that even if they delete the comment from their profile, it is still out there somewhere- and could be recalled at a most awkward moment.
There is always the danger for those with low commitment, that they will flirt with people on facebook or similar sites- and may even have a completely different persona online. Paedophiles can also potentially add minors as friends, if said minors falsify their information when creating an account. One of my "friends" on facebook is an 8 year old boy, but the profile is not accessible to him- his father monitors it, and is going to close it because of the shocking number of comments from random weirdos.