Current best-practice eschews the "new" keyword on Javascript primitives. If you want to create a new Array simply use brackets [] like this...
var myArray = [];
You don't need to tell Javascript how many items to size the Array for. Javascript will automatically increase the size of the Array as needed, as you add items into the Array. Creating an Array with brackets instead of with the "new" constructor avoids a bit of confusion where you want to initialize only one integer. For instance.
var badArray = new Array(10); // Creates an empty Array that's sized for 10 elements.
var goodArray= [10]; // Creates an Array with 10 as the first element.
As you can see these two lines do two very different things. If you had wanted to add more than one item then badArray would be initialized correctly since Javascript would then be smart enough to know that you were initializing the array instead of stating how many elements you wanted to add.
Since the new constructor is not necessary with Arrays and there's a slight chance of unintended results by using the new constructor, it's recommended you not use "new Array()" to create an Array.