The major difference between this version and the previous (0.1.9) is that this one is likely to be easier to get working with Zope 2.7.x. Before, with Zope 2.7.x, you might have needed to set a special environment variable.
The slimmer function is vastly improved I think. Less optimizing on HTML files but much much faster.
Read about the slimmer module on ZopeLabs.com