I include metadata for all of my Daz Products here at Renderosity. I have found it personally to be incredibly useful in the pipeline of creating an image so it is worth the extra time to include it in a product. 

I understand with vendors such as Sickleyield there would be an extensive backlog to wade through due to the shear volume of  products she has on offer. It would be good to see it as a requirement for Daz Products though I would worry that it wouldn't discourage vendors from adding that Daz Compatibility as another process is added to their work flow. 

Which is probaly why this is best dealt with on a community level.

I think that creating a place for sharing metdata for Renderosity products is a great idea.

Maybe a sticky at the top of this thread. Nudges forum moderators.

I have to say also that cridgit's tutorials are pretty good. At first its a lot to get your head around. But after a while its a straightforward process. cridgit has also helped me out a lot in the past with providing metadata for my products.