The PS4 was announced yesterday, 2/20/2013, it was immediately pummeled by the media and on social networks. I think that this might be a touch premature. Why? I'll list out a few different reasons and let the reader decide if I'm off my rocker.
First, streaming to the PS Vita. Commentators have already compared this to the Nvidia shield, while I think this is accurate, I think that misses part of the point behind this capability. The true purpose is to get people used to the idea of streaming a video game from one system onto another system. We are used to doing this with video already, but we aren't used to truly playing something that is entirely run on a different system than the one we're interacting with.
Second, play while downloading. This feature is again to help us get used to the idea of streaming a game from a server. Sony acquired Gaikai a while back which enables playing a game on the server. Initially offering only server side play while downloading is a very safe way for Sony to test system requirements on the server side, manage capacity needs by limiting the amount of concurrent users, and developing an understanding how game play feels when thousands of people are playing the same game over an internet connection.
Third, console gaming systems have always had lower specs than the bleeding edge PC games. However, the platform is stable and encourages developers to figure out new ways of exploiting the technology. They don't have to worry about continually changing systems. On top of that, the developers will eventually begin to exploit the combination of the CPU and GPU using OpenCL and figure out new ways to eek more out of less using that technology.
Fourth, in 5 years it won't matter what is underneath the hood of the PS4. Not because no one will be playing it, but because Sony will have acclimated users to streaming over the Vita. Sony will have acclimated users to streaming from a server through downloads. Sony will have determined server requirements to host all games and stream the game to the PS4. It's likely that there will be some experimental games that will allow playing both client side or server side, but eventually there will be a game that will only be server side. It will be a big game and it will begin to push all other games to the server. At this point Sony will have optimized the hardware for the PS4 to display higher quality game play coming over the internet.
The PS4 is not the next console for Sony, it likely could be the "last" console for Sony as it develops new ways for users to access games and continually "upgrade" their console as the server side technology for game streaming continually matures. This of course eliminates the need to sync a disc to a specific system and even removes the need to download any content. You buy a short cut and you can play immediately.
So, is the PS4's hardware going to be kill the PS4? No, the hardware on this system isn't the point. The goal is to allow access to games that will be streamed from the cloud.