Just ressurecting this thread because I now own the Mighty Mouse! I couldn't resist, I had to try it for myself and figured I could then report back to share whether it was worth it. Keep in mind that for a while now, all I've been using are either the trackpad on my laptop (single button, ergonomically painful for my thumb) and a cheap two-button mouse I got free from some vendor at a conference (it looks cool because it has blue liquid in it, but it's the old kind with a ball in it that sticks even when it's clean). I haven't used the old logitech trackball in a while (the one with the maroon, marble-looking trackball) because the response to that was sometimes sluggish; don't know if it was the trackball or the mac, so just stopped using it.
So, I've been using my new Mighty Mouse for all of a few hours now.
Okay, first impression as I took it out of the box, "Oh no, maybe this isn't what I was hoping it would be." Now, this is before I had it plugged in or anything. I was just pushing buttons to see how they felt and thought the scroll ball thing that also functions as another button was incredibly easy to press down, so anticipated trouble scrolling without accidentally clicking! And the side buttons you squeeze give no sensation of motion when you squeeze them (or very subtle), so I was wondering just how hard they needed to be squeezed to work. I was also not entirely convinced that something that looks like a one-button mouse really would function smoothly as two buttons.
But, I proceeded to plug it in and install the driver (I was a little surprised at having to do this; somehow I expected this to be plug and play with the support already built into OS 10.4... based on the way it was advertised, but okay, this is hardly anything to get flustered over).
So, I got it all installed, cranked up the tracking speed and double click speed (if you haven't figured it out, I'm a speedy sort of person...no sluggish mice for me...if you want to move your mouse halfway across your desk to get to the other side of the page, I'm not the person to give you a review that will predict your experiences). Like any multi-button mouse, I had the option to set what I would use the buttons for. So, I set the standard left and right clicks as primary and secondary buttons (given the shape of this sucker, if you're left-handed, you could easily switch those if it would be more comfortable for you, but I'm right-handed, so stuck with the traditional). As for other functions, I don't really have anything that I would need a 3rd or 4th button for, so decided to try some of the featured options. The default for the scroll ball button is to open and close dashboard, and the default for the squeeze button is to activate expose (expose is the feature that let's you either clear the whole desktop with the press of a function key so you can get at stuff ON the desktop, or you can tile all open windows to find something you're working on that you've buried under a bunch of active windows). I decided using a mouse for something I don't use much anyway, and that can be accomplished with a single keystroke already wasn't really useful, so set the scroll ball button to switch between applications. So, now it pops up in front of whatever I'm working on a menu (with big icons...I don't know if I can change the appearance of that yet) of all the currently open applications (as opposed to my dock that shows all applications I put on it that I can open them from), so I no longer need to scroll down to the dock to switch applications. This is a minor advantage, but I think when I'm really busy with multiple applications, it'll be something I'll really grow to appreciate. I wasn't sure what else to use the squeeze of the mouse for, so set that to dashboard. It didn't work quite the way I anticipated, but I actually like it better. I expected it to work like hitting F12, click once to open dashboard, click again to close it. It worked that way when I used the scroll ball button for dashboard. But, when I use the squeeze button for it, it just opens dashboard when I squeeze, and closes as soon as I let go. Obviously, if you have widgets you use often that you need to click on or type things into, this won't be a good use of this button. But, for me, I like this because I can quickly glance at the calendar, time (I have a few clocks for different time zones so I know when to call people), whether I have new mail in gmail (Yes, I now have that...I wish when everyone was offering all those invitations around here they had explained more properly how it worked as different from other online emails...I love it!), and weather reports, and then let them just as quickly drop out of the way.
Okay, so, in contrast to my initial impression out of the box, this mouse is great (at least this is my impression after only a few hours of using it). The scroll ball button is actually not something you press by itself, but you click the whole mouse while pressing on it (like a middle button on a 3-button mouse). So, that alleviated that concern...I cannot accidentally click just by scrolling. The scroll ball is very much like a scroll wheel in having that "clicky" feel to it, which I like (though, when it's quiet, the clicks are audible too, if that's the sort of thing that might bother you). I feel like I have more control than I expected to have with it (I was afraid I'd be going every which way until I learned to control a tiny trackball type thing). I haven't yet opened anything that had a scroll bar in more than one direction, so haven't tested the multi-directional scrolling aspect yet. I'm on the hunt for an oversized picture to give it a try. Squeezing the sides does require a little more pressure than I expected at the time I bought the thing, but not as much as I expected upon removing it from the box. Considering where my fingers wind up while moving the mouse, this is probably a good thing to avoid accidentally pressing that button. Right and left click work perfectly as expected. No delays in response to the mouse either. I've had problems with optical mice from apple in the past (the single button ones that come stock with most macs) in that they don't always operate smoothly...despite the claims you don't need a mouse pad, I've always had problems with them "skipping" if I don't use them on a mouse pad. But, this one doesn't seem to have any problems with that. It seems to be working equally well on a TV tray as on a sofa cushion (yes, I'm working at home today), so they must have gotten something fixed.
One thing about the scroll ball that contrasts with my experiences with scroll wheels on windows machines (but haven't used them enough to really say this is a difference...it could just be the applications I use them with)...this one seems to just know when I'm in a window within a window. For example, if I just place the mouse over this quick reply box, I can scroll up and down within the box. If I move outside the box, I scroll up and down on this page. If I scroll to the top of the quick reply box and don't stop scrolling, it switches to controlling the whole page. With Windows, I often have to click on the scroll bar I want the wheel to work with if I have multiple scroll bars on a page (such as this reply box within a page).
So, I give the Mighty Mouse a very positive review. I have ONE complaint though. As is typical of apple mice, the darn cord is too short! The USB port on my PowerBook is on the left side, and once I have the cord run behind the PowerBook so the mouse in on the right side to use it, there's very little cord left to spare. I know, normal people usually have a mouse plugged directly into a keyboard and keep the two close together, but I have a tendency to put the keyboard in my lap (keyboard trays are never a comfortable height for me, and just bang up my knees that don't fit under them...I don't know how you taller folks manage) and keep the mouse on whatever work surface is nearest (desk, table, etc). Then again, if this mouse works so well on a sofa cushion, I may not need to concern myself with that issue, and I have an extension cable if I need it.
So, I give the Mighty Mouse two trackpad-weary thumbs up!
I'll update this report if I discover other good features or problems as I use it more.
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