What was it about Locke and Eko that made the SS not view them as threats? Was it told to leave them alone because they'll play a more important role down the line?
I got a crazy idea the other night based on the ABC preview of Locke, Sawyer and Jack standing around the fire. A few of The Others show up, tell them that Walt is fine but they want a trade: Walt in exchange for Locke.
And of course Locke goes with them and we get the next Locke-POV episode from wherever he's being held.