As one of the primary brawlers on this topic, I've already said enough about it, so I will restrain myself and just say that I fully support the proposal.
Well, mostly restrain myself... I will make one comment about what John said below. Although it is true that a CollectionObject (or "evidence") would probably need to have been derived from an organism to be relevant in the Darwin Core context, there is no reason why a CollectionObject cannot simultaneously serve as evidence that the Organism existed, that an Occurrence occurred, and as support for an Identification. Particularly in the case of specimens, it is likely that the CollectionObject will usually serve all three purposes at once. A CollectionObject could actually serve as "evidence" for anything you want. To some extent, that's one of the reasons for decoupling PreservedSpecimen from Occurrence.
For more pontification on this subject, I will refer to http://code.google.com/p/darwin-sw/wiki/ClassToken (where Token is equivalent to what John is calling CollectionObject). The first figure on the page illustrates diagramatically what I said in the paragraph above.
Steve
John Wieczorek wrote:
and exclusion has been voiced. The basic idea is to use this class to cover information that could be considered "persistent evidence" that an organism occurred, and that the concept is distinct from both "Organism" and Occurrence. Evidence might include collection-based materials, digital media, written materials, and literature.
"Evidence" may be a bit vague as a name for the class, providing no real indication that the "Evidence" should apply to an "Organism" rather than to an Occurrence, Taxon, Identification, or any other class. Nor does it convey the idea that the evidence should be persistent. "PersistentEvidenceThatAnOrganismExisted" gets the idea