In the congressional hearing last night someone said 10 meters. This figure was from army medical examiners.
The original story had the main U.S. force firing on an unknown group from down in a gorge, but that story I think has evolved over time.
Here's an interesting article which delves into it.
[A href="vny!://www.opednews.com/articles/opedne_bill_per_070730_was_pat_tillman_murd.htm"]vny!://www.opednews.com/articles/opedne_bill_per_070730_was_pat_tillman_murd.htm[/A]
The contention voiced in this article is that there is no way you could fire a 3 round burst and have all round impact so close together. Not only is there muzzle drift to take into account, as the article states, once the first round impacts the target is going to spin and flail. So it's asserting that a single round killed Tillman, then after he was dead 2 more rounds were pumped into him to make sure.