IMDB like forum (means LOTS of forums)

[carlatf]

Hi,
I'm planning to do a forum like the IMDB one. Which means it will be a lot of forums. I'm not sure if I should use SMF or made a forum system from the scratch. It will involve automatic creation of thousands of forums. Can this be done with SMF?.
All the forums are loaded in the memory?.
Many thanks.
Carla