Large solution files are difficult to manage and navigate in Visual Studio.  When implementing new features a developer often has to jump between a handlful of files that can be nested deeply across multiple folder or even projects in the same solution.  The Context Navigator is a new type of solution explorer that will only show you the files you need, along with other context specific  information such as bookmarks and break points while hiding everything else.  A multiple contexts can be saved, loaded, and even checked in with the solution to allow other developers in case they need to go back mopnths later and fix something.