What are the 3 most popular social networking sites for teenagers?

Hello, for ICT homework, I need to know what the 3 most popular networking sites for teenagers are, and how much users use them. I need to know before tommorow, so please be quick :) thanks.What are the 3 most popular social networking sites for teenagers?
I would say Facebook, Myspace and Twitter.What are the 3 most popular social networking sites for teenagers?
myspace- 263,043,083


http://www.myspace.com/





facebook- 200,000,000


http://www.facebook.com/





msn- 120,000,000


http://www.msn.com/





:)
um myspace, facebook, and twitter.





Although many people use AIM and Bebo
I think that they are MSN, bebo and facebook coz me nd ma fwends all ave dese. Hope dis helps
myspace, facebook and bebo
my first choice will be Orkut,,,,,,,,,,,,then Facebook and Myspace.