I also could live with having another slice just doing media serving. If I could share the filesystem or run some rsync script, in some efficient/non-cumbersom

I also could live with having another slice just doing media serving. If I could share the filesystem or run some rsync script, in some efficient/non-cumbersome manner, between the media server (threaded apache) and app server (main box with php etc) that could work and would allow more parallelism, as they say, for faster web pages. Then again you have the same problem with things like drupal, that just plop media all over the place and it's up to the client to maintain the separation of media in their code. Drupal users don't do that.