An interesting PS5 article is here.

Use google translation.

http://pc.watch.impress.co.jp/docs/column/kaigai/1066148.html

Also a possible scenario. I'm thinking Sony is considering PS4 and PS5 crossplat support. Hence, they could share a lot of content for a period atleast.

PS3, Vita and PS4 shared a good amount of content even though their specs differ significantly in arcitecture. PS4 and PS5 would be able to share content easily assuming they stick with the same arcitecture. That would make pushing PS5 a little less risky because they wouldn't be killing of PS4 immediately.

Yeah, that's how I'm seeing it too. Of course we could both be wrong but to me it makes sense and I feel as if Sony will want to drill home their lead and so garner more support (early on).

I'm sorry but that sounds even worse.  Not only would the leap probably leave a lot to be desired, this also discourages 3rd parties to take advantage of it and instead ride the PS4 even more than they did the PS3 at the start of this gen.  Plus, without exclusives to show the power of the system, it would probably sell at a slower rate than the Pro.  And for what?  A small arbitrary lead over a system that may never materialize from an opponent whose brand has been in bad shape for ages?  With the PS4 being a highly consistent, powerful seller and the Pro offering extra bells and whistles for the 15 to 20% of potential consumers who care, this is an all risk, virtually no reward scenario.  

Unles the Xbox One X truly does revive the Xbox brand in a major way (unlikely) or the Switch causes a big drop in PS4 sales (even more unlikely), Sony will ride the gen until the PS5 can blow your socks off.  It would be illogical not to.

The problem with the Pro is its pretty much just a PS4 with a more powerful GPU and a modest CPU upgrade.

The X1X is a more viable 9th gen contender given the even more powerful GPU, its CPU upgrade is more significant on paper, and the RAM avaiable to games is almost doubled.

Regardless, I don't think the PS4/Pro is dead when PS5 hits. As I suggested its still gonna share games with PS5, maybe Sony will really push crossplat support. To some developers the PS5 might be the PS4 Pro 2. But X1X has more potential as budget 9th gen hardware.

Generations and their timing are generally dictated by leaps in the tech landscape. The next big one that home consoles are aligned for and would justify a new generation is probably AMD's upcoming 7nm APU's. When they're ready for Sony, they'll be ready for MS too, whether that's 2, 3, or even 4 years from now. Their base hardware will probably be the most similar any two competing consoles have ever been, so they'll try to differentiate themselves in other ways. Sony may double down on VR and streaming while with the rise in popularity of virtual assistants I think MS could really take advantage of Cortana, beefing her up and making her integral to the console from the start.

That is tough to see. As Nuvendilis saying, the impact of tech over time is getting smaller. A PS5 in 2019 is going to be very unimpressive, and very likely turn consumers off. We are talking a turn around quicker than PS3 to PS4, and people are expecting a $399.99 console. Add together the slowdown in tech development, the necissary leap required to give it next gen wow, inflation, and PS5 would be significantly less impressive than PS4.

I just can not see another generation of consoles limited to HDD, and SSD won't be cheap enough until 2020 at the earliest, thus leaving a 2019 next gen in a really weird position. I think a much better play would be to release an optional PS4 Premium in 2019, and then release a true next gen PS5 in 2021 or 2022.

PS4's chip set at 7nm with a few more modernizations like the Pro saw, will deliver 4K and 60fps on many titles. Give it 16GB of RAM, and it will be a perfect last push for PS4. Then let PS5 be the 3nm 20+ TFLOP, 128GB of RAM, SSD based storage beast of a machine it needs to be, delivering an unquestionable leap over PS4, PS4 Pro, and PS4 Premium for a true next gen expereince. This will allow it to maintain 4K/60fps while delivering a massive leap in every graphical department that will be evident to all.

Regaurdless, PS5 has to be backwards compatible with PS4 software. We will be closing in on 50% digital or surpassing 50% digital sales depending on when PS5 is launched. With iOS and Android kind of setting the standard, people expect all of their digital content to continue to work on their new devices.

Yeah, it's not exactly the same, I have to agree, though I think mindsets are changing as the strategies change.

Around twice what the scorpio is, and 4k should be no problem at all.

The question is then, if we really need that much? or should they try to keep prices down on the device instead?

Nope. Late 2019 or Late 2020.