Declare variable and assign initial variable value in a single statement in SQL Server 2008

In SQL Server 2008, you can declare variable and assign initial variable value in a single statement.
Instead of using DECLARE and then SET commands like this:

DECLARE @variable1 varchar(50)
SET @variable1 = 'Test'
SELECT @variable1

...you can declare variable and assign initial variable value in a single statement:

DECLARE @variable1 varchar(50) = 'Test'
SELECT @variable1

The initialization of the variable to that value still happens at execution time.