See http://blogs.msdn.com/jasonz/archive/2009/02/20/a-new-look-for-visual-studio-2010.aspx for some snapshots of the new VS2010 user interface. Some things I like:
New support in the editor for outlining: Colors on margin indicating edit status, triangle glyphs, ellipses.
Improved New Project dialog: online template viewing, a search box, easier navigation, multi-targeting includes .NET Framework 4.0 as an option.
New Extension Manager: many third parties have built extensions to Visual Studio and now VS2010 will provide a robust management tool to better find/integrate/manage extensions. See http://www.visualstudiogallery.com and http://www.codeplex.com/site/search?projectSearchText=%22Visual%20Studio%22%20%22extensions%22 for some examples.