The first is the copy an entire site function.  This allows admins to copy an entire site and can be reached from the manage site --> general --> copy site.  An extremely useful feature where you can make a site in a test environment and then publish it to a new production environment.  You can also use the feature to generate site templates - lets say a school has a default look and feel for teacher web sites - a default can be created and copied at the start of the school year for each teacher.

The recent announcement gadget has a major enhancement in the ability to control how much text and a thumbnail option.  Previously the recent announcement gadget displayed a pre-defined text limit and didn't bring across any type of a picture/thumbnail.  Those text parameters can now be tweak and a thumbnail of the first photo will be displayed within the announcement block.

Searching within the site just became a bit stronger with the ability for the admin to control what happens when the user enters in a search parameter.  The new controls allow for searching within multiple sites so that a user can pick up information from multiple sub-domains.  For example, a school can setup the search parameter so that a single search can find information from all the school's website's located on the domain.  The search configuration is located under manage site --> site layout --> configure search.

Finally, an old friend returns - originally there was a start page that was included as part of the Google Apps experience - a place for each user to host their own definable start/home page.  Later, the start page was removed from Google Apps as they felt that the same could be achieved with a personal site within the user's domain.  While that's still true, there is now a template called "start page" which will allow the user to easily create their own user definable start/home page.

Complete details with examples can be found on Google's blog.