For what it's worth, Courtney Taylor and Koren Robinson are listed as the starters on the Seahawks website. Listening to talk radio today, though, they're saying that while Koren does seem to remember a great deal of the playbook, he's not exactly in the best game shape after being out of the game for this long. Also, while Colbert is definitely in better shape than Koren, he's not all that familiar with the playbook.
Based on last week, though, I don't think that the receivers not knowing the playbook is going to be THAT huge of a deal. Hasselbeck targeted McMullen several times despite it being his first week on that roster. I think that you'll likely see a rotation of Koren, Colbert and Billy McMullen alongside Taylor. Bumpus will likely get a few looks, as well. I see a heavy dose of Carlson this week, though, and don't necessarily think that it's worth it to gamble on a Seahawk's WR unless absolutely necessary.