That format doesn't really work well for poker...too much variance week to week, so the random luck element would be a bit strong. A 16 person weekly bracket lasts as long as a monthly contest, but the monthly contest is more likely to be skill-based.
I've recently done some playing around with different formats that add some meta elements to the game and are a blast, but require the ability to track stats more closely than possible for anyone but an SBR admin (if their software even supports). If (and it's a mighty big "if") I can get a platform working well enough and I can either find the time or automate it sufficiently, I might have something a bit more interesting to offer later in the year