we can print objects to the Console window when the object is a very simple.
Object Dumper is used if the object has many properties, only the properties that contain values that are not null or collection of objects, or an object graph with depth of more than 1.It can print simple to complex objects and object graphs in a single line of code.

Check out this link,
http://blogs.microsoft.co.il/blogs/bursteg/archive/2007/10/25/all-about-objectdumper.aspx
http://blogs.msdn.com/b/ericwhite/archive/2008/08/14/object-dumper-an-invaluable-tool-for-writing-code-in-the-functional-programming-style.aspx