I've seen examples of throw that use Error and new Error:
throw new Error('new Error')
and
throw Error('Error')
i.e.: 
(function(){ throw new Error('new Error') })()
(function(){ throw Error('Error') })()
(cut/paste in console to see that they both work)
Is there any reason to include the new?
I ask because I think throwing Errors is preferred to throwing strings .. better stack trace I think, but if the new isn't needed, I'll drop it.