Checking out some social networking sites

Currently I am a member of Facebook and Hi5. I checked myspace.com today. They all have pretty much the same features such widgets, applications to be downloaded, privacy settings, broadcasting, etc. What is different to me is the age group to which these sites cater too. I noticed My Space.com and Hi5 are populated mostly by teenagers and young adults while Facebook seems to be more adults between 25 and 40 years old. I dislike that some of these teenagers or young adults even the adults like to upload inappropriate pictures or say inappropriate things. Other than that they fulfill the purpose for what the sites are needed. My favorite site is Facebook just because all my friends are there.