The new classifications file is an evolution of Alienvault/Emerging Threat's work to provide a new structure of classifications to the Snort Community in order to define better priorities and descriptions for the classification names that were proposed.
We ask for a review of the descriptions and priorities, provide comments on the blog entry linked above, and we'll take a re-look at it after January 12th.
As a side note: There has been a lot of conversation on the mailing lists about the classification system as well. Even a suggestion to rewrite the classification system entirely. Which we aren't ruling out and may be the best solution.
But we'd love to hear your comments!