We have just uploaded WP e-Commerce 3.6.8 RC1 for download.
Depending on the community response over the next few days (week max) we will look at launching the full 3.6.8 version asap. Once this has been uploaded we will start focusing our efforts on the next 4.0 release.
Just to summarise; we have greatly improved the overall User Interface, Product Groups have fully replaced Categories and Brands, new SEO improvements include pinging your Update Services, Stock Keeping Unity (SKU) has been added to the product Meta table, and links to corresponding support pages have been included in almost all of the WP e-Commerce admin pages.
More information and screenshots will be provided when we properly launch 3.6.8, I must say I'm very proud of this release and if you want more information now please refer to our Forums or view our SVN Revision Log hosted at wordpress.org.