Now, I don't have a 70-200, I've got a piece of shit 55-250 (Get's the job done [better than nothing], mind that) and Tamron 17-50 among other lenses.
I say that you get the Tamron. It's imperative that you have a more versatile lens, such as the Tamron. I mean, the image quality and physical build quality of the Tamron in comparison far surpasses that of the kit. You can use the Tamron in more ways, and while you won't be able to film surfing as well (or at all), you'll have a fantastic lens for just about anything else. It'll come in handy 10 times to 1 compared to the tele.
My 2 cents.