Not much to update other than this tweet by Michael Cunningham:
#Hawks F Marvin Williams (back bruise) won't travel w/team for West trip. MRI scheduled
Doesn't appear to say that he will miss the entire road trip but at the very least he won't be with the team in Oklahoma City. Marvin was injured when he flipped over Lou Amundson during the second half of last night's game. Will update this when more information becomes available.