Meet the
DualShock 3. Announced recently at TGS 2007.
Here's what it looks like:

Looks familiar, huh? Looks kinda like the last controller:

Which kinda looks like the last controller:

Which resembles the last controller:

Which has some similarities with the controller before that:

I'm not gonna be one-sided with this. I'll point out the not-so-obvious changes to the controllers...obviously, they added analog sticks and rumble to the DualShock 1 (though the right stick was never used for anything, really). DualShock 2 added analog functionality to all the face and and shoulder buttons. 'course, the fact that these buttons were shallow and really had no depth made it so that it was very difficult to use in anything but a racing game. Seriously, MGS2 and 3's controls sucked 'cause of the pressure-sensitve buttons. Then there's the wonderful SIXAXIS tilt controls that brought us masterpieces like Lair... Oh yeah, and the rumble went away, too, but at least it's wireless (and not that proprietary bullcrap that Microsoft pulled). And uhh...they changed the second set of shoulder buttons into triggers...cool I guess? Then the DualShock 3 comes along and brings back rumble. HUGE innovation. I'm sure other companies will copy it!
But the button layout has remain unchanged. Yeah..., you know what they say, "Don't fix what ain't broke." Well...first of all, that's not grammatically correct. Second of all, the DualShock is already "broke." Fix the damn analog stick placement, Sony. >=[