I know a little, I will add what I know to what I read here and other places...
Summing up, in no specific order
There is a Turbo inline six coming. It will have bleeding edge tech. it will almost certainly be three liters displacement. It will almost certainly be turbocharged. It will almost certainly have tech to erase turbo lag, that also adds power, and helps add efficiency especially in low RPM situations where turbos lack efficiency. It may share some parts with the Hurricane 4. It will almost certainly be offered in two or more configurations and two or more power levels. I have been assured that the only folks who will be dissatisfied with its output is our competition, and keyboard warriors who always seem to have that rusted out, clapped out, blow by having, oil burning '77 RS/SS/Z28 Camaro that runs 9's on pump gas.
The config that will be its bread and butter will be in Jeeps and Rams (and Ram Commercial) were the 5.7 simply is no longer a good choice, or won't fit, or is not the right engine for the market. This engine is supposedly going to make Jeep/Ram look much better in worldwide markets. Char-llenger will get (at least) one version. I am VERY pleased with that (no I wouldn't say anything even if I did know anything). It will replace the 5.7 in some/all applications. I don't have visibility for the future of the 5.7. If anyone claims to have that visibility just assume they are talking out their ass, unless it is a known good source (of which I am not). The long term future of the other V8's is secure. The 5.7 (in my opinion) will stick around for at least a while, until it is longer a financially viable engine (business case for it falls on its face).
I am ASSUMING that SRT has version of this new engine. I also assume that SRT has done some real world testing of this engine. Those are pretty safe assumptions. It also a darned safe assumption that SRT is getting MAD power levels out of it. What is not safe to assume is if anything SRT is working on will make production. I do know that there is something (or somethings) very cool squirrelled away in the SRT skunkworks. No, I don't have a clue what it (or they) is (are). I could guess, but I'll hold that until we all know more.