Saints running back Pierre Thomas went through limited practice for the second day in a row on Friday. However, it's still no sure thing that he will play this Saturday in Seattle due to a chest injury. He is listed as questionable. In the same game, Seahawks wide receiver Percy Harvin is listed as probable with his hip injury.
Thomas will be a game-time decision, and if he can't go, Mark Ingram will face tough sledding against the Seahawks.
It looks like Harvin will indeed see a healthy number of snaps against the Saints. Still, I wouldn't expect it to be more than 40. There's enough uncertainty around both situations here that I'd rather avoid them in favor of safer options.