A good console name shouldn't need explaining, it should be clear and concise to all who glance at it.

Hopefully Sony don't wait too much longer to pop the hood on PS5, I'm curious to see what they're bringing to the table. 

Xbone/PS4 are old now and were never really interesting to me to begin with, so I'm more than ready to see what's next.

2001: Xbox

20055: Xbox 360

2013: Xbox One

2020: Xbox

My guess is that we'll get an announcement event in Feb, like they did with the PS4.

Also, now that XSX is outta the bag, I imagine Xbone sales are gonna be looking very limp in 2020. If it had weeks in the 40k range this year without a revealed successor, these next few weeks may be the last few of sales relevancy it ever gets.

Digital Foundry's take:

https://www.eurogamer.net/articles/digitalfoundry-2019-xbox-series-x-reveal-analysis

Could be 2X (120mm?) axial fans on the base and top. Enough for reasonable cooling and temps, but positioned horizontally inside to blow air down instead of up.

Hot air only rises naturally because cooler air is naturally higher up, when it's calm. If you create a vacuum/pressure, pushing cooler air through, the heat will go wherever the cool air passing by does. If they point the fans down, the cool air will come in from the top and hot air will go out the bottom. By the time that exhausted air reaches the top again, it would likely be room temp, so no big deal. This way, even if the floor is dirty around the console, it will clean it for you by blowing it away instead of sucking it up.

PS4 and XB1X were built upside down internally. The majority of the heat from the APU's was trapped on the bottom of the console. It didn't really matter though because as long as it's closed off tight enough, and cool air is passed though in a large enough volume, or fast enough, the heat will be absorbed by the cool air and will exit the console. PS4 just used a smaller fan due to internal space, which meant higher RPM's, more noise, and more dust. Which eventually leads to even higher RPM's, trying to pass air through even faster, with even more noise, sucking in even more dust.

It also could be that there's just 1X (200mm?) on top, blowing up, but massive and slow. With it being on top it won't suck much off the floor, but would still pull in cool air. If it's big and slow, it will cool by using a larger volume of air, and not by passing smaller amounts of air though as quickly as possible. It may even have a filter on the bottom in this case, but it wouldn't be a great filter because that would restrict too much airflow.

With how quiet it's supposed to be, two worthy size fans running reasonably slow, or one massive fan just crawling along, should allow the console to remain quiet and cool. 

From a PC perspective it would make sense to have a fan on the bottom pushing air and a fan on top pulling air, aka. "Push-Pull" fan configuration.

That would then make it like a wind tunnel... And is generally the preferred way you set up say... A PC heatsink fan configuration.

Hot air generally rises because of thermal expansion.

I.E. When you warm a gas (I.E. The air) that gas then expands and becomes lighter overall. - That then rises up and cooler denser air sinks down.

Should be fine... I would assume they would employ some PC technology to mitigate the dust issue. - I.E. On startup the fans spin in the opposite direction for a few seconds to exhaust dust.

Otherwise some compressed air should do the trick or whack a dust filter on the consoles air intake.

Push pull would likely be preferred yes, but more so if the fans were blowing down. If they are blowing up, sucking from the base, depending on how much pressure differential they are creating, and how close the base of the console sits to the floor, dust could certainly be an issue.

Thermal expansion, yes. As the air goes up it deals with less pressure and loses energy, making it cooler. When it's windy out though, depending on how windy, the hot air will mostly go sideways, but also up. The difference is an open space is quite a bit different than an enclosed, if not sealed space. Not to mention controlled vs constant variation. An enclosed controlled console, in an enclosed controlled building, with fans blowing down through the console, will receive little to no thermal expansion resistance. The entire room will have roughly the same air pressure and temp, so forcing air down though the console would be easy, depending on how the internals are laid out.