I think the forum should stay as is.

This forum is kind of like a Bitcoin Museum that was built by Satoshi, and we should leave it that way (I realize its already different from the first iteration)...

I just can't imagine coming to a hip, modernized forum to read Satoshi's initial posts...

The forum gets the job done: people are free to express themselves any way they so choose...

Spam will always be a problem so long as there are sig campaigns and bounties, regardless of what software they use.