The one bonus I found so far is the increased dialog between editors, in an
effort to improve the new articles. This can only be beneficial.
I'd personally recommend extending this to a week long trial.
Currently, an IP is either banned or unbanned. What if we had a middle
ground for problem IPs, which didn't allow them to create new articles, only
edit existing ones. It wouldn't be a cure-all, but it might be interesting
concept to play with.
Nick