don't use new in Javascript

JavaScript, We Hardly new Ya » Yahoo! User Interface Blog

You never need to use new Object() in JavaScript. Use the object literal {} instead. Similarly, don’t use new Array(), use the array literal [] instead. Arrays in JavaScript work nothing like the arrays in Java, and use of the Java-like syntax will confuse you.

Do not use new Number, new String, or new Boolean. These forms produce unnecessary object wrappers. Just use simple literals instead.

So the rule is simple: The only time we should use the new operator is to invoke a pseudoclassical Constructor function. When calling a Constructor function, the use of new is mandatory.