This is a topic on what is important for a "good" social networking script without consideration to what is currently available. If one were to define a good social networking script, what would be the most important elements? I'll list a few. A good SN script should have:

Profile Page
includes friends system
includes comments system
modifiable layouts
SEO friendly profiles e.g. mysite.com/myname

Blogs
It should either have it's own blog system or be able to integrate with a good multi-user blog system such as lifetype. Most recent blogs should show in the user's profile.

Gallery
Again, it should have it's own gallery system or be able to integrate with a good gallery system. Recent pictures to show in user profile.

Forum
Most internal forum systems such as Drupal's forum or Joomla's forum are not as good as a standalone so the SN should be able to integrate with a standalone forum such as vBulletin. It should bypass the forum's profile page and display the SN profile page.

Front Page
It should show most recent members and random members. It should also have at least a simple CMS so the administrator can add site news and information.

Any other suggestions?