No game used all of the buttons but Cybermorph and hoverstrike used most of them.  Doom made good use of them, each weapon was mapped to a different key.  Iron soldier used 1,4,7 and 3,6,9 for weapon selection.

Technically considering motion controls and IR allow the wiimote to basically work in a 3d world doesn't that mean it has infinite amount of inputs. Just saying.

You forgot one, the Intellivision!  16 buttons and that crappy disc.

That controller was not designed well. After a few days the disc started to tear the skin off my thumb and I had to put on a bandage so I didn't bleed all over the controller. The buttons were all destroyed in a few months because the thin plastic wore through and got torn.

Anyways, the OP lists controllers from successful consoles of each generation. There were many experiments that failed. Adding random buttons doesn't work, they have to be put somewhere that makes sense. It also helps if you give them nice bright child-pleasing colors like the GC controller.

Ultimately more buttons only appeals to the hardcore gamer and developers, since for the developers it means they can add even more input options and for the hardcore gamer it means more complex games are possible. But to a non-hardcore gamer, the only thing that's really important is that the games are fun. To that end, more buttons is actually a detriment.

Buttons are just a single feature of many to consider. There are several values inherent in a controller: grip, complexity, ease of control, and intuitiveness. Let's look at each.

For grip, consider: the Atari 2600 joystick is really uncomfortable to use compared to the NES pad, which is mildly discomforting compared to the SNES pad, which is a bit lacking in extra grip compared to the PlayStation or N64 controller (though some prefer not having those grips). But that's about where the evolution of grip ends. We have gotten "good enough" for grip, possibly a bit over "good enough".

For complexity, consider: the 2600 had 1 button, and was considered very simple. The NES had 4 buttons, and was considered easy to use. The SNES had 8 buttons, and was seen as a bit tricky to get used to at first. The PS1 had 10 buttons initially, eventually expanded to 12. A lot of people I've shown a PS1 or PS2 controller to say it looks too complicated. So we've not only hit "good enough", we've actually overshot it.

For ease of control, consider: the 2600 joystick was stiff and largely unresponsive. The NES d-pad was comfortable enough, but lacked non-linear/analog precision. The N64 analog was quite suitable, if a bit too loose. The PS1/PS2 analog was also quit suitable, but a bit too tight. The GameCube analog was pretty much spot on. Nobody has made an an input method yet that overshoots the market, so presumably we have hit "good enough".

For intuitiveness, consider: the 2600 controller was very abstract; you gripped a stick and wiggled it around, and stuff happened. The NES d-pad was slightly more intuitive, but still abstract. The N64 and PS1 analog sticks were again slightly more intuitive, but still had you doing something you wouldn't do normally. For intuitiveness, we still have a long ways to go before we hit "good enough".

Now let's look at how the Wii Remote measures up to these values.

Grip: Closer to a SNES pad than an N64 or PS1 pad, when not counting the Nunchuk
Buttons: 7 on the Wiimote, 2 on the Nunchuk. Closer to what the SNES had.
Ease of Control: The pointer and Nunchuk analog stick both provide pretty standard control input that's easy to use.
Intuitiveness: Motion control is leaps and bounds ahead of the intuitiveness involved in moving an analog stick around, as is the pointer.

So what we get is: grip and buttons are behind the curve, but at the "good enough" points. Ease of control is right on par with the rest of the controllers out there, which also appears to be at the "good enough" point. Intuitively speaking, it runs circles around other controllers.

What we actually have with the Wii Remote is taking away of elements that have overshot the market, and improving elements that have undershot the market. In that sense, the Wii Remote is miles ahead of every other controller on the market that's trying to push more buttons, more analog sticks, and so on.

 Selectively lists controllers from succesful consoles. Gensis, Saturn, and the Playstation were all left off for some reason. It also ignores the fact that the keyboard has been out longer than most of the controllers on that list and has always had far far more inputs. Despite that consoles have been gaining ground compared to it for years and now is at the point where people can falsely claim PC gaming is dead and often not get called on it. The number of inputs has not steadily grown from generation to generation. Rather it has varied wildly with the average number of inputs increasing. The Wii has not deviated at all from this. It has more or less stayed the course once you include the motion sensing abilities of the wiimote and nunchuck along with the IR function.

Nobody likes the DualShock according to this site.

Its useless for racing games, FPS, third person games, sports games, wrestling games, dvd control, just about anything according to some people.

The N64 controller was the best. I was aroused by the sexy analogue stick

Like Fishy Joe said you really need to take in the type of input in to account when you talk about the evolution of gaming.

For example: sure the DS touchscreen may only count as one imput, but you could map buttons to positions on the screen (ala Elite Beat Agents) and it effectively creates several more.

I need another hand to fully enjoy hardcore gaming. Dual keyboards is the future.

That looks sweet. :)