Your guess is as good as ours. I would kinda assume the Bendis DD omnis WILL be reprinted at some point, since they've already reprinted the Miller and Bru ones.
As far as Bru Cap, that's more tricky. Again, I would THINK they would reprint the 1st three omnibuses, BUT I doubt they would do them all at the same time.
So you might see the first volume one year, "death of" the next, and "Lives" the next. Again, totally just a guess.
the other issue with Bru-Cap is the TPB collecting of it is a total mess. I would think they might just go the route of the "complete collection" ala Bendis' Avengers runs right now, and collect the entire thing in 5 or so large TPBs. But again, no one really has much of a clue.