Instagram's answer to Vine's six-second video clip phenomenon launched a week ago. Given the fact that the image sharing service already had a wealth of users before the addition, one has to wonder what sort of impact it has had on Vine over the past week.

Whether or not Instagram Video is a blatant copycat of Vine or not is irrelevant right now. What is worth mentioning is that Vine has become one of the most successful apps in the US as more than 10 percent of iPhone owners are now using the service. But how has Instagram Video affected that?

It's still a bit too early to know for sure but here is what we have to go on right now. Looking at the US iPhone download chart for free apps, we see that Vine went from second place all the way to seventh between last Thursday and this past Sunday. This is noteworthy as Vine hasn't fallen out of the top five since March 27. What's more, the app dropped from third place to tenth in Mexico and went from fifth to twelfth in the UK.

Keep in mind that this is preliminary data and isn't entirely reflective of how many people are or are not using Vine these days. What it does show, however, is that a lot of people are now downloading Instagram Video to at least try out. Will users stick with the new software, revert back to Vine or perhaps use both programs equally? Only time will tell...