Final design, any suggestions?

Over the last weeks I’ve been trying to workout a design for a project. I’ve started with a design and realized while implementing that it was flawed. I’ve been getting a lot of help here and I think I have my final design now. Any suggestions or criticism are welcome.

I created a design diagram. The double lines represent m2m relationships, the arrow is a foreign key relationship with the arrow pointing to the parent model. The bold names are apps, the entries below are models. Abstract models are in italic.

The basic functionality is this. Users can enter events and contacts. They also can upload or link differtent types of media. Some events are displayed publicly on the website, others are internal. Blog entries can be created for files, events or independently. All media and (public) events gather in the database and can be accessed by visitors.

I haven’t much experience designing databases so I can point to this resource where you can find some example here.