Team site, the bread and butter of SharePoint …
Well, this video goes over some of the major differences and some of the pain points that have been resolved in comparison with previous SP versions. Some of the highlights in SharePoint 2013 Preview Central Admin screen cast are:

1.  8GB of RAM totally sufficient for SP2013 dev environment
2.  Central Admin pages look almost identical to SP2010; app management has been added
3.  You can now customize Central Admin pages!
4.  “Site Actions” has moved to the right hand side again
5.  “Everything” is an app … wanna add a calendar – it’s an app.
6.  Team site editing is in a WIKI format
7.  Better tablet experience by having a button to remove nav and menus
8.  Drag a drop multiple docs right on to the page to add them to a library
9.  Ribbon is still here, but there is lesser focus on it; very smart move
10.  Cleaner document properties UI, no modals so better for tablet

Enjoy!