I haven't heard any official word on this yet but I'll give my opinion. I think the impales will be back primarily because we've all seen that Nightwolf's arrows stick in your constantly, I'm pretty sure the swords will be too.

I was noticing that the arrows were sticking around, but they do eventually disapear. Also, they don't cause any extra damage. I think his arrows are more of a visual effect.

However, I haven't seen any of the new weapons have this ability yet, so I figured I'd ask.