Obomanu is possibly the most well-rounded player in the Seahawks receiving corps. He can play any of the three positions, and can contribute on special teams. Still, the front office may want to make room for a younger player or keep additional players at different positions that require his roster spot.
Butler is in a similar place to Obomanu. He is an NFL caliber receiver that will be on a roster somewhere this season. It just may not be in Seattle. Butler is not a special teams guy, although he has tried playing some on coverage this pre-season.
Durham was a touted prospect as recently as last year. No longer. The team is said to still like him, and he is practice squad eligible. It would not be shocking if they got a 6th or 7th round pick in 2013 or a even a 5th in 2014 for Durham since he is still young and has some unique measurables.
Washington still has plenty of value for a team needing a secondary runner and playmaker. This would open up a spot for a guy like Kregg Lumpkin or Vai Taua.
Signed as a free agent this off-season, Omiyale does not look good enough to make this squad. There are plenty of teams in need of offensive line help that could be tempted to acquire him via trade so they don’t have to compete for him on the waiver wire.