What are the main advantages of upgrading from Microsoft Dynamics NAV 2009 to 2013 R2?

I have often heard NAV developers and consultants say that there are immense advantages of upgrading from Microsoft Dynamics NAV 2009 to 2013 R2; Can anyone enlist me the top few.

there is a defined upgrade path. follow it and all is ok.

http://msdn.microsoft.com/en-us/library/dn271649(v=nav.71).aspx

http://msdn.microsoft.com/en-us/library/dn466744(v=nav.71).aspx