Why would you want a SSD inside a console?
With the PS3 and its really shitty bluray drive installing games on the HDD was somewhat required. And the PS3 HDD (at least the one in the PHAT was a joke. When I installed it into my laptop and tested it, It was like 40mb/s whereas my 2008 computer HDD was like 150mb/s, The stock harddrive was utter shit.
A normal (non stock HDD in case of Sony installing CRAP again) HDD will be more than sufficient for what the PS4 will do. Its not like console games are like installed PC games with 100000000 files. The only advantage you will have is installing the game on the SSD will be faster and if you are lucky starting the game will be marginally better. The games wont run noticeably better etc.
And I doubt that this is worth the extra money. (The biggest gain comes from replacing the shitty stock harddrive with a good one.)
But if you still dont want a conventional harddrive in your next console buy a hybrid drive. SSD seek times with $/GB price ratio of normal HDDs.
btw what exactly do you expect from upgrading to a SSD?
