A friend of Wilson says Wilson had his gun out, yelled “Freeze!” while Brown was running away, then Brown turned around and ran toward Wilson as if he were going to attack him.
http://www.freerepublic.com/focus/f-news/3193375/posts
Eyewitness video conversation confirms that Brown did turn back around and head toward Wilson.
At this point, it looks like a valid shoot to me, but what do I know?
good find.
He met the Imminent Threat threshold.