Social Services Sites

Now, social services are gradually moving from comprehensive to more thematic.

For example - classmates, and ilovecinema.

Vertical - means
Horizontal - themes

However, the lack of thematic lies in their vertical limitations.
For example, on ilovecinema you can only write reviews on the blog. At the same time, a person who is interested in cinema, and they want to discuss books about cinema, video materials, etc.

The closest to this is the model of the social network platform (facebook), which allows multi-format, as many developers create services for users.