Having worked on Squarespace version 5 for almost two years, and grown accustomed and sometimes frustrated with the few limitations of the platform, I was very excited when information started trickling down that Squarespace version 6 is in the works and will offer complete control customization of templates along with the ability to develop new templates from scratch. Squarespace v5 offered basic (colors, font-size, background etc) as well as intermediate customization (changing layouts, resizing widths etc) to the end user through an elegant WYSIWYG editor that let you view the changes in real time. The result was that end users were able to create websites that looked different from the standard, run of the mill templates. Indeed, I was very impressed by what some of my clients had done with their Squarespace websites before they had approached me for further customization.
However in Squarespace v6, after choosing an initial template (from a limited but beautiful selection), the end user is left only with the basic customizations at his or her disposal.
The inability to add HTML code at different points of the template (a major feature of v5 which helped customize websites) as well as the complete absence of the robust file manager of v5 has made the current state of the platform very limiting.
Squarespace v6 does offer complete control over the underlying code through the developer mode (which is currently in beta). That is all well and good for developers who know how to code but it adds little value to the end user who has little knowledge of the languages that drive our websites.
Squarespace v5 was a right step in the direction of making website developers redundant for creating simple, elegant websites but that process has been stopped by the introduction of v6. Squarespace v6 is no doubt much more powerful than v5, but the bulk of the power has been placed in the hands of the developers instead of the end user.