Mike Elgan posts "The Mouse Is Dead" on Earthweb today.  Its the perfect example of why people who haven't actually looked at the design issues involved shouldn't judge the mouse.  In his article he suggests a few "mouse replacements"...

1. Apple's giant trackpad with multi-touch.

Available on MacBook Air and MacBook Pro laptops, this pointing device represents a body blow to the appeal of using a mouse with an Apple mobile computer. The new trackpad is superior because in addition to pointing and clicking, you get gestures, which adds a whole new layer of control.

2. Gaming pointing devices.

Remember when everyone used to play games on a PC using a mouse and keyboard? Neither do I. Console gaming has re-set the bar for gaming input devices, and now even PC games seem to call for joysticks, yolks, steering wheels and other non-mouse input devices.

3. "Brain-reading" devices.

Like the mouse between 1963 and 1981, these devices are still in the lab. But one company, Emotiv Systems, plans to place a $300 headset on the market by the end of this year that lets gamers control some aspects of games with thoughts alone (go here for the demo).

4. Apple iPhone and the "iPhone Killers."

This newest category of cell phone boots physical keyboards and phone pointing devices (like BlackBerry's "pearl," toggle switches or the tracking sticks on some handsets) altogether in favor of full-size touch screens. Although people tend to see iPhone-like devices as replacing keyboards, they're getting millions of people used to the idea of controlling an entire operating system with a touch screen.

Now a few of these I don't think are even worth of mentioning.  Most serious gamers still use a Gaming mouse and the "Brain Reading" device is a helmet which no one is ever going to wear so I think you can safely rule those two points out.

But what I wanted to focus on is Touch.  I'm bullish on Touch interfaces and  have been working a lot with TouchScreens from Elo Tech lately.  I've deployed about 8 of them serving different purposes around the campus at this point (mostly as Timeclocks/Kiosk applications). 

But here's the thing, Touch is not effective as a mouse replacement.  This is for a few reasons...

1.  Accuracy goes out the window with Touch.  Here's what I mean...

Anyone who has accidentally clicked on a link while using their iPhone can attest to this fact.  Touch is great with alternate interfaces where everything is made really big but it sucks for day to day use because the finger just isn't accurate enough.

Some might suggest that Multi-Touch fixes this by allowing you to size screen elements and that is partially true.  But while Multi-Touch might fix this particular problem it still means you're having to use 3 gestures and both hands to do what the mouse now does with one click. 

2.  Touch creates a problem when dealing with multiple angles.  This doesn't become apparent until you actually try it but if you touch something on the screen while right in front of it and then stand up and touch the same thing while looking down on it you'll actually be hitting different parts of the screen.  Because your viewing angle of things on the screen changes while your finger (which is outside the screen) stays essentially the same.  This happens every time you change your viewing angle and it makes touch ineffective for anything but relatively short uses.

The mouse is on the screen just like all the other elements so it doesn't suffer from this problem. 

3.  Range of motion is tiring.  Notice that, when you use your mouse, you are really only moving your fingers and your wrist.  The reset of your arm is pretty much at rest.  Now pretend to use a touch interface and watch how quickly your shoulder and upper arm get tired from all the gesturing, reaching, etc... 

The truth is there are a lot of issues with a touch interface that simply make it unusable with current systems (which were all designed around the mouse).  Someone may some day find a way to design an OS based around touch but until that happens the mouse is here to stay (and since I don't see a dramatic shift to an OS that no one has even invented yet happening in the next few years I think its safe to bet against Mr. Elgan here)