It really depends on whether or not our universe is within the event horizon of the black hole. If our universe was inside the event horizon, I imagine an outside observer would see something like we observe when looking at a black hole that is pulling matter off a star, but the matter in this case would probably be more like planets, moons, stars, etc. In this case, we would probably have already observed the phenomenon as a big black spot in the sky. We might also have noticed the disappearance of all that mass, it is possible that we could miss it, however. The universe is a big place. If our universe was ouside the event horizon, then an outside observer might just observe our universe to be orbiting the black hole (with other universes?). We, on the other hand would notice nothing, as we cannot yet view other universes(if they do indeed exist) to note that they are changing position. This is just me thinking the problem through, it's not based on fact or anything, so don't take my word for it. Sorry I can't be more help.