SquareSpace has announced that they are going to be accepting applicants for beta testing of the new, upcoming version of SquareSpace CMS. According to the blog post:
Squarespace V6 is a reinvention of many core Squarespace concepts that will become the foundation for our company over the years to come. It allows the extremely talented folks who work on Squarespace to create the sorts of sites they've always dreamed of creating on Squarespace. It incorporates a totally redesigned consumer editing experience, backend site manager, and template system.
Some sneak peak screenshots of the upcoming templates and the new interface: