What are the differences between the enhanced Seller Center and the old Seller Center?
For a seller, the platform is basically a copy of the old platform - just with a strong foundation, prepared to support you as a seller even better.
Small Interface improvements has been included, like sales overview in the dashboard of the front page - there to assist you as a seller to gain an better overview of the performance of your business.
The only functional change is on content, where you can now use already approved content to have a more efficient and structured approach to uploading and managing your content. The already approved content is referred to as a SPU, under which new SKU's can be created.