If I get a iPhone 4 now will it have iOS7?

I'm getting a iPhone 4 for Christmas, I was just wondering since its a brand new device will it automatically come with iOS 7 or will I still have a opportunity to stay on iOS 6?

Chances are you might get an iPhone 4 with iOS 6. Just check the Manufacturing date or the box. If its before iOS 7 realease date then its iOS 6.
You can upgrade it to iOS 7, but you won't get all the features which iOS7 has in iPhone 4s, 5 and so on.It'll be a light version of iOS 7.

Yes it will come with iOS 7.0.4 (assuming that remains as the latest version between now & then)

Yes, it comes with the latest iOS version, 7.