I like the ideas.
But I think the post requirement should be much lower. Something like 10 to 25.
Also, I agree with many here that the shoutbox is not really THAT important, since you can go to IRC if you want to avoid excessive SPAM.
But for those who want to stay there or can't go to IRC, a little screening wouldn't hurt anyone.
And I agree with FineWolf that the skinning system should be improved to allow images and (maybe even) name coloring.
/ 
