I don't think they will bother, at least with the PS4, not for these particular tasks anyway. My guess is Sony has their money on GPU compute for doing advanced physics and things of that nature. One of the biggest customisations of the PS4's GPU is actually the compute specs, perhaps the only part of the console's hardware that is actually pretty advanced, comparable to the R9 280X in that respect. Resogun, an indie launch title by a tiny team, uses GPU accelerated physics to push up to 500,000 voxels in destruction, on screen at any one time, at 60fps no less. This is actually way beyond the number pushed in example voxel destruction demo's using better hardware, at 30fps instead of 60fps. So with the right optimisations, there are alternatives. How it will stack up to cpu side cloud compute I have no idea.
There are definitely alternatives, but it won't reach the level of what Crackdown 3 does in multiplayer. It's just not feasible, and really, isn't feasible on either console no matter the optomization. It is possible on Xbox One due to the cloud, but without that, it's nothing. PS4 can use that same cloud if they so choose, but given how they are handeling PSNow, I would say they are going to avoid that route entirely.
The interesting part to me is that everyone I have heard of that saw or played this game... there isn't a single one that wasn't blown away. Let's think about that for awhile. Some complain the resolution isn't that high or maybe there is some AA issues or this and that - reality is, everyone who is touching this is like... this is something they haven't seen before. Going beyond what we've seen even on PC games. Virtually going "next level".
That's pretty neat. To think a game can get universal praise like this because it's doing things that no one has seen before the way it is actually being done. Just a crazy thought that we've finally got a game that is proving itself right in front of people's eyes to be something truly next level. Truly never done before.
Will it get overhyped because of this? Sure. Will it live up to most people's expectations? Probably not. Will it still be impressive and beyond anything we have seen on a game console? Probably.
Does this mean Xbone > PS4? No. Does it mean the Xbone has an exclusive doing something the PS4 isn't? Sure, and unless Sony sucks it up and decides to hop on Microsoft's cloud structure, it may always remain that way.
More importantly, if this ends up working live as well as it is working at gamescom (and that's a big IF. PSNow worked great in small things like this too, but publicly it hasn't been as smooth in full testing), it's literally proving that microsoft wasn't full of it when they boasted about this possibility years ago. They just needed a studio to actually decide to use it.
Of course, there are limitations with cloud stuff. There probably always will be. But it's recognizing those limitations and just using what the cloud is most capable for over what your local box can do, or in conjunction with, that is going to feel great.
However, the real question is if this ever becomes a norm, or just something a handful of titles plays around with. Time will tell, but it's nice known that in a controlled environment at least with 11 servers, what is happening looks and feels special. No matter if you're a sony, microsoft, nintendo, or PC gamer (or heck, mobile device gamer), you have to just appreciate the effort of doing something no one has done before and getting a result that is that good so far.