I think the Samurai makes for a great survivor type, but as far as focusing on the deathless line or negative hitpoint play I don't think it's productive. The Samurai has his resolve to play with and when that runs low he just needs to play less aggressively. I've seen it in play, however, and it was pretty good.
One bonus for the Samurai is that he can use his resolve right away for more than just damage, he also mitigates missed saves which is an option these guys don't get (without feat investments which are hard to justify).
I would say the barbarian build will destroy the samurai in late levels for going and standing in the worst possible place taking massive damage. The Samurai will be better than all builds in the first 5 levels and shouldn't need to invest feats in survivability, relying on his resolve to keep him around.