From Concrete5 on their new release:
We completely changed the way installation works so it is much easier to build a starting point. You can even install completely from the command line. We also took the time to rethink Scrapbooks which had evolved “organically” and had any number of issues. Now there’s Stacks which let you clump different blocks together into one reusable element. Permissions, versions – everything you’d expect from a concrete5 page all work on a Stack. Very cool.
Some other features that have been added is the ability to navigate to administration tools. A feature that we like a lot! Also we are a big fan of some of the ways that the new Clipboard (a tool that kind of replaces the scrapbook) works.