I suggest that a heavily moderated "Best of Forum" subforum be created at the top level.
As "Best" precedes "Bitcoin" alphabetically this forum would be the top of the list when you visit http://forum.bitcoin.org/
At the moment, certain threads start out as a succession of high quality, information rich, well formatted posts and after a while they get diluted by lots of posts of lower quality.
Threads could be nominated for inclusion into the "Best of Forum" section and any replies to the threads would have to meet high standards to be approved.
The "Best of Forum" would be the logical opposite of the "Newbie" forum and would serve as an example of good forum contribution and participation.
If a post contained worthwhile content but was not formatted, spelt or referenced correctly then the writer would be asked to amend it before it was included.
Certain contributors of good standing would have the ability to post new topics directly to the "Best of Forum" but if they abuse this privilege then they would be liable to lose it. Most of the time, contributors so entitled would only choose to do so if the topic was likely to be of significant general import.