I'm hoping that there isn't a PS5, there's kind of no need for it, especially because it barely feels like this generation has begun. The endless graphics race needs to stop, please.

A PS4Portable would be neat though.

I don't think Sony will be able to abandon the PS4 library going forward like they did in the transition from PS3 to PS4. (Microsoft doesn't much more credit since the feature was added later when they were struggling). Never the less Sony as started a trend with the PS4 Pro was it a one of? Or is the future of console gaming just hardware whenever need to match customers expectation. Therefore, it really doesn't matter when the PS5 comes out, it might actually never be a PS5 more like a PS4.5.

I think at this year E3, Microsoft will announce that they will be adding Xbox original games to backward compatible. Therefore Scorpio which kinda start a new generation for Microsoft will be home to all Microsoft consoles games going forward. It's definitely something that Sony need to look at and would do well to copy. Gamers don't want an overpriced streaming service, especially for game they bought in the past.

My guess is with 2020 Sony consoles in general have a long life. No point for Sony to abandon that since their platform is big enough to keep third party support till 2020 anyway even if the big third party titles run in 720p by then. In 2020 the tech is also far enough to significantly upgrade from the pro and make a machine that can actually run in 4k while pc's are running games in 8k for €400-.

The PS5 will be probably PS4 pro backwards compatible.

My prediction is 2020.

2021 would be ideal but I feel they don't want to give MS a chance to launch early so they'll target 2020.

3 full years now is January 2020. So if they launched October 2020 it would be 3 years and 9 months. Basically this gen would have been 7 years. The perfect length.

And yes the ps5 will be a true 4k console and I feel this tech will have matured nicely by then. TV adoption of 4k should be good by then too.

...I have no idea.

Naah, Scorpio will not do significant, So it will not affecting PS4 sales , hell even i bet PS4 Pro will have more sales then Scorpio. 2019 is the perfect year to release the console , but in 2020 is even better because AMD tech already mature enough to release " AMD Navi "based GPU into console market.

Agree with u, they probably going to make exclusive games  for Pro, but dont expect to see exclusive Pro games before the end 2018 or 2019. 

I think highly debatable at this point if there will be anything that can be defined as a next gen. Either incremental upgrades or a shift away from dedicated consoles altogether. maybe one more gen left?

Earliest fall 2018
Latest fall 2020

It sure looks like PS plans on 6 year cycles with 3 year mid gen upgrades, but Scorpio will most definitely affect this timeline. The sales of Scorpio will determine the outcome.

Sales that surpass Pro and make PS4 weak in the knees could mean a late 2018 PS5.
Sales that only compare to Pro, even slightly more, will most likely mean late 2019 PS5.
Sales that can't even compete with Pro could mean a late 2020 PS5.

A $399 PS5 late 2018 would not be a good situation. However, a $499 PS5 late 2018 wouldn't be near as bad since it would be out of some gamers financial reach, forcing them to wait to get the new console or upgrading to a Pro for the time being.
As long as BC and FC is kept, then PS can justify it because they can fall back on Pro since it will be affordable and won't be as drastic as a drop to PS4.

I would have to assume PS would rather get a full 3 years out of Pro and launch PS5 late 2019, but would also be willing to wait an extra year and reap/milk the PS4/Pro rewards just a little longer before PS5 in late 2020.

2020 seems like a reasonable timeframe, a 7 year (or is it 6 year, I can't be bothered doing the maths?) console cycle is pretty traditional. 2018 would be too much of a rush considering Scoprio is only out at the end of 2017, and not a big enough upgrade on PS4Pro (i.e. price for better tech). So earliest I would say is 2019, which is only 1 year earlier than what would be reasonably expected anyway.