Sometimes things just go very convenient and we wish that how come it was not available in earlier versions.
Let us see two features here. If it was SQL Server earlier versions we might have to write more lines to achieve what we can achieve in lesser lines. Following small example with only one variable demonstrates this feature.
SQL Server 2005 version:
DECLARE @idx INT
SET @idx = 0
SET @idx = @idx + 1
SQL Server 2008 version:
This version demonstrates two important feature of Inline Assignment and Inline Operations
DECLARE @idx INT = 0
Reference : Pinal Dave (http://blog.SQLAuthority.com)