Random impulse, traded in my PS3 Slim at EB Games today, got $85 after bonus, covered the taxes and then some.
One word I would use to describe the PS4 is smooth. Think of the PS3's OS as sandpaper and try licking it. Now think of the PS4's OS as ice cream and try licking it. World of difference But seriously, it just runs so smooth, very snappy. And the games (demos so far) look pretty good. Definitely looking forward to the first racing title that appears.
Right now I have a few PS+ games like Dead Nation, Contrast and Don't Starve installed. Will try those this week. I also have the FIFA 14, and LEGO Marvel Super Heroes installed. Will give those a try sometime as well.
One thing that really impresses me (and disappoints at the same time) is the Dualshock 4. It feels infinitely better than the DS3. Light, responsive, and the sticks feel great. Not loose like the PS3. The triggers are improved, though still a bit small compared to the 360 and X1, but definitely an improvement over the PS3.
BUT, that lightbar on the back of the DS4 is really annoying and is killing the battery. I also noticed the controller didn't go into sleep-mode while watching a blu-ray. Wonder if that's by design or a bug?