(Unrelated to my post in suggestions about forum priority)
I have marked some threads in Global as low priority. When I am in Sneak Peek, they appear to have normal priority - a triangle pointing to the right. (For me, these are the transfer thread and the latest scrimmage thread.) If I click on one, then the thread displays and the box at the top says that it's low priority. (There are no triangles in the list of threads since these are stickied. However, this isn't limited to stickied threads, as I just "low prioritied" the day trading thread and it appears in the sneak peek as normal.)