I believe I said this before, but I personally don't see a difference (at least not without major concentrating) between a locked 30 and 60 fps, BUT I feel it while playing.
I do see diffrences between 24 and 48 frames so I must be able to percieve higher framerates, but once it gets over 30 it becomes very hard for me to see.
Now while actually playing it makes a world of diffrence.

I noticed it the moment they looked down at the ground, 5 seconds in. The eye can pick up the jump in movement easier. When more detail stuff is in the frame.

The real question is if a game was only 30fps would you still buy it or just say, hell no, 60fps or no buy. For me 30fps is just fine. For people who think it is impossible to play at 30fps obviously are very new to video games, or just think they are special and "can see the difference" because they haven't always been 60fps and were still enjoyable. Kind of the same way I actually like 60hz TV better than 120hz and higher, they make everything look like I am watching a soap opera in my opinion If just being 30fps makes games easier to develop and release sooner that is great with me :)

I can usually see it, but most of the time I don't really care. There are many aspects of a game that are infinitely more important to me than its framerate.

I can see the difference between both and I think 60FPS in a game is important but not necessary. Games with 30FPS are still enjoyable. But I really would love to see all games running in 60FPS next gen. ^^

Can you see the difference yes
Is 60FPS better yes
Is 30FPS unplayable NO
Should more games be 60FPS on consoles, not necessarily, since we love Uncharted 4 SP graphics

It's pretty obvious in that video - almost surprisingly obvious, since I've often heard the claim that stable 30 FPS should be pretty much equal to stable 60 FPS. I didn't fully buy it, but I thought it might make the difference considerably less noticeable.

Also, high framerate is not just about the graphics. It's even more about how smooth the game feels. Often, games don't just render at a certain framerate, they also play at the same framerate. With 60 FPS, that's about 17 ms per frame. With 30 FPS, it's about 33 ms per frame. 30 FPS adds a noticeable amount of input lag. In fact, in some games even 60 FPS is sub-optimal.

You can see the difference if you compare them next to each other.

When you have a gaming habit on Multi GPU...its hard not to notice the difference.

I can see a difference...but I can't give less of a shit honestly.

I remember playing Clive Barker's Undying on my TNT2 and just barely having 10-15 FPS most of the time. Made shooting down flying enemies a pain in the ass. Feeling was awesome.