I haven't really looked into the details of the Ps3 and Ps4. I'm a PC gamer but my bro and I were thinking about buying a PS3 to play our old games and some new ones. Ps2 graphics weren't too good, I'm not too sure a Ps2 game would look so different when ran on a Ps3; but what matters mostly is the reverse compatibility. I hear the Ps4 isn't getting that, and apparently as mentioned above Ps4 is requiring a fee for online play. If I do own a Ps3 game I might just check out the multiplayer for the hell of it really so I wouldn't plan to pay for membership.
Growing up we owned a Ps1 and Ps2. Personally, I'm very comfortable with the Playstation controller setup which is probably the second reason why we never considered the Xbox (the first being our Playstation games). Google imaging the ps4 controller, it looks pretty boxy. Can't say till I actually try it out.