No new multi-threaded games come anywhere close to fully utilising 10 cores. We're at the point where some new games actually use 5-6 cores, no more. Hence the 10900k will not come close to 90C during normal gaming, and will be able to turbo high
The extra cache will help it further extend Intel's gaming performance lead.
I wouldn't assume its going to turbo much higher than a 9900K with out some really expensive cooling.
This isn't about temperature and we need to stop thinking about it as hot vs. not hot. Its about the cooling requirements and what temp it will run at, at that spot. Now in regards to the 10900k, we look at the power usuage of lets say the 3900x or 3950x. They don't actually use max power at max load. They both top out at about 8c (16t) full usuage and that's because of other limits outside just temp. That's were core usuage, core speed, and power usuage hits its max and it starts leveling off after that.
Anyways. As the cores try to clock higher for having less of them used. I suspect it will be much the same unless MCE is turned on. So at defualt settings at 6 core usuage we could be looking at max power usuage. That max usuage is looking north of 200w, specially if you are able to use TVB. But the problem with TVB is its use is basically going to be hotspoting an area, making TVB limited on that point. But to even hit that the CPU has to be running rather cool. That's where the problem comes in. If its thermal throttling with a 280 AIO, will a 360 work. Will we need custom loops. I think we can mostly agree that a D15 or H100i are the on the extreme end of coolers that we can "recommend" for desktop chips as 99% of the CPU's out there its way overkill. But I think there is a point that if this chip starts requiring $150-200 cooling or more, to run in spec, without slamming up against the thermal limits of the chip, there is problem, or at least can be mocked for being "hot".
In the past we have gotten review where the reviewers went straight to AIO's because Intel doesn't ship coolers with their CPU's and not accounting for that when comparing to other CPU's. With the 8700k it was as it was brought up there probably a wash. Less so on the 9900k. But I think specially with this guy it will be important for the reviewers to figure out what "adequate" cooling will be like comparitively.