I think it is fake, well, actually is it, i know there is a lot of videos out there, I checked out cokementos.com, all the videos don't look like hoaxes, but i don't know in the video above, are you sure it is just not some sort of vinegar and baking soda trick?

any thoughts

One sunny, very hot afternoon in Las Vegas, a bunch of programmers decided to try this. With 5 2-liters and a pack of mentos in hand, we walked across to the new parking lot (to make it sticky with diet coke) and watched the experiment unfold.

I didn't do the editing...it would have been much better if I did it ;)

It didnt' look like the photo above but some were performed as promised.

You know its fake, lol. This is accually real. It was performed on Mythbusters the show on Discovery channel, they we trying to see how far they could take the Mentos+Coke experiment. They have even been able to get the spray from the coke with a mentos to go 34 feet while holding the bottle down and making a narrow exit for the cap. That pic/video above is straight from the show I saw today on Mythbusters and thats why I checked it out.