Nearly three months into 8th gen, I'm really enjoying it so far, with a couple of slowdowns because I'm sometimes sitting in front of the PS4, trying to figure out what to play. It has to do with the fact that I'm playing like 2-3 games daily and I have like 7 of them still, not counting the digital FTP's.
Even if it's not a graphical leap like PS1 to PS2 or PS2 to PS3, graphics are still solid and at a level we can expect from it. My only major complaints is the PS4's controller battery duration. Sony really needs to release an improved controller without the light bar and better build quality, since the left stick is already veering a bit to the left. There's also the occasional lag here and there, and an occasional feeling of games not being entertaining after completing them, but that might be just me. That might be it... for now.
There are some already released games I really want to get, like inFamous Second Son, Assassin's Creed IV Black Flag (I doubt I'll get Unity and Syndicate), and double-dip for Sleeping Dogs. I can't wait for Fallout 4, Ratchet & Clank, Horizon, Uncharted 4, No Man's Sky, the next Mass Effect, Hitman, among others. I believe there's still a lot more fun to be had with the PS4.