Should have mentioned this in detail, but the PS5 likely follows a traditional console design. There's going to be a blower-style cooler with vents all around the console likely being intakes, all exhausted out through presumably the rear. In effect, it's a lot like the PS4 Pro, just packaged in a different shell.
The good news is that it's much larger than the PS4 Pro, which would mean it has a massive heatsink and likely also a larger blower fan (or two). So, I'm relatively confident that the acoustics will be fine - just given the sheer size of it.
If it was a compact unit with the usual console design, I'd be more concerned.
The PS5 can be laid horizontally, and since the vents are on the edges rather than the bottom, it shouldn't affect cooling too much. Though definitely vertically would be the ideal configuration.
It may be a good cat warmer in that case :P
I have my PS4 Pro right next to my PS3, right next to the VR box for the PS4. There's not much room on that shelf in my entertainment unit. I might have to build something new to accommodate everything and handle the absolute warren of cables behind the cabinets - my entertainment unit looks like a server cabinet gone wrong - and the PS5 would look ludicrously out of place - but... I'm a tragic for the PlayStation exclusives at the moment - even with a powerful gaming PC...
You could replace your PS4 Pro. PS5 should run all PS4 games, and run most of them better. (They do add a caveat that some corner cases there may be some issues, but not clear what that means...)
I'll be doing that - most likely on launch - have some "gift cards" from some flights that were cancelled due to, as Steve puts it "human malware".
Just waiting on local pricing and orders to start - I'll pay the early adopter tax, provided the unit has support for the PSVR gear I already have - otherwise, its a hard sell to dump my PS4 pro.