They announced it in both TechCrunch articles.
Apple has announced they are working on a Mac Pro and new monitor.
No one has announced a new iMac. Anything you read on it is idle speculation and wishful thinking—what, a thousand threads now including this one?
I expect the Mac Pro to be more powerful and more expensive. Look whom they're building it for and what it's expected to do. I expect it to begin where the iMac Pro leaves off. If it's not $15k for the base model including the new monitor, I'll be surprised.
The iMac Pro is the upper mid-level Mac. It is neither as expensive nor as powerful as 10 Minis with eGPU linked together crunching a file ($40k) but that is the level of performance that Apple must be aiming for with the Mac Pro—or why bother? Apple's competition in that market is a couple of Win 10 boxes with prices from $15k–$150k (depending on configuration) that already exist.
No, that's not how hardware pricing works.
Apple will pick one of two options:
1) Mac Pros support dual CPU set ups, iMac Pros are single CPUs. Both are Xeon-class CPU machines.
2) iMac Pro was just a hold-you-over option while they worked on the Mac Pro, and it dies.
If it is option 1, then a Mac Pro will likely have two of these:
https://ark.intel.com/products/134859/Intel-Xeon-E-2186M-Processor-12M-Cache-up-to-4-80-GHz- or similar in their base spec, going all the way up to 42 cores or so in a maxed-out option. The processors at a base model then combined go for about 1,300$.
If Apple supports dual GPU (like in the 2013 Mac Pro) then we can expect two Radeon VII GPUs, combined going for about 1,500$.
Add 32GB DDR4 ECC 2666 MHz RAM for about 800$
And a 1 TB SSD for another 500$.
Factor in the Apple case, PSU, and motherboard for about 500$, and we arrive at a grand total price for a Mac Pro sans monitor:
4,600$ (dual GPU dual CPU)
"But this is cheaper than the iMac Pro..."
No duh, it doesn't include a monitor, and has almost double the capability of the base model. This form factor is immensely cheaper than an AIO build. This is why unless we're talking about Apple, an AIO is a really bad option for a computer.
Now if we include a monitor on the price scale of a LG 5k UltraFine, we're looking at a ~7,000$ machine. It would not surprise me though, if option 2 is possible.
If option 2 is possible, the base model of the Mac Pro will be single-CPU, single-GPU. That drops the price down to ~3,350$ for the Mac Pro sans monitor.
There will be advanced configurations that certainly scale up to 15,000$ for sure. But that will not be the base model.