I chose "review" because of "spiegel" - that's as snappy as I can get with this.

or:

(online) supplier performance ratings (directory)
(online) supplier performance site
supplier ratings forum (site)
supplier performance forum

seems harder than I thought because anything with board can imply a "review board" of one company, and supplier system is a software also for a company to evaluate its suppliers. Also, supplier performance index is taken:
http://www.google.com/search?q=supplier performance index &b...


Now, if it's anything like our blue board it would maybe have the characteristics of a "forum."

So I thought of supplier rating(s) forum
unfortunately, not too well supported either.

And snappy - well, not really.

Here is an example of an online ratings site:

http://www.asicentral.com/asp/open/MemberBenefits/supprate.a...
Supplier Performance Ratings

Supplier Performance Ratings reveal how a supplier does business, based on the collective experience of the distributors who've worked with them. Ratings are averaged across each area and updated every 24 hours, revealing the most accurate and timely picture possible. A numeric score and star rating (up to 5 stars) is calculated based on performance in the following areas.



https://www.alcoa.com/howmet/en/info_page/pdf/suplperf.pdf
performance evaluation