Take this from an owner of 20+ Logitech mice and 2 of Apple's Mighty Mouse...
Mighty Mouse is a love-it-or-hate-it product. If you're accustomed to resting a finger on the right mouse button, Mighty Mouse will drive you bonkers, as it won't register a left-click then... the miniscule scroll ball is actually pretty nice, it's 4-way, and scrolling horizontally the same way you scroll vertically is great (Logitech has tried a hundred different designs for sideways scrolling but all of them have been flakey).
Lately I've been using a wired Mighty Mouse for my laptop (I normally use a Logitech VX Nano which is awesome, but tiny), and I'm actually starting to appreciate its soap bar look-and-feel... it's an old one that predates laser, just standard optical tracking with a bright red diode, but I like it.
The wireless Mighty Mouse, however, sucks. First there's the weight. It's only 2 AA batteries but it feels 5 times heavier than the wired version. Normally I like a heavy mouse, but the thing is that the mighty mouse doesn't have those nice slippery feet you'll find on a Logitech Mouse. Instead it's got a ring of hard(ish) plastic around the base, and it's got somewhat of a sharp edge. If you have a hard precision surface of glass or metal you can feel the wireless Mighty Mouse scraping against it like nails against a blackboard. It feels like you're chiselling off little bits of either the mouse or the surface. Also, it's ludicrously overpriced considering how primitive it is. You'd think with all of Apple's battery research they'd have introduced rechargable Li-Ion mice and keyboards long ago, but no, it's back to the 1990's with AA batteries that run out in no time (the VX Nano gives me about 90 full workdays with two tiny AAA batteries, the Mighty Mouse gives me 30 days tops with two larger AA ones). Also, the tracking on suspicious surfaces is miserable. And it's extremely sensitive to interference on the 2.4 GHz band, if you have a wireless home you'll often find when using the Mighty Mouse that the mouse cursor grinds to a halt for no apparent reason. Finally, there's a bit of lag as well (Bluetooth has nothing on Logitech's proprietary 2.4 GHz wireless technology).
Here are my picks:
Precision work: Logitech G9 (or the new G9x). It's a wired mouse but it's just stunning, not only for gaming but for graphic design it's simply wonderful. If you're wireless crazy, I suppose you could get the Logitech G7 which has the same precision and also allows you to switch the sensitivity on the fly with buttons on the mouse, but prepare yourself for a lot of battery swapping (it comes with two Li-Ion batteries, you charge one while using the other), at least 2 times daily. And also it doesn't have Logitech's nifty 'free wheel' scrolling like the G9, MX Revolution, VX Revolution (dud!), VX Nano etc. The G9/G9X is very much a desktop mouse, though, the cable is like six miles long and very stiff, very inconvenient for laptop use.
2nd choice for precision work: Mighty Mouse wired.
General purpose: Logitech MX Revolution. It's a very nice mouse, what can I say, you already have one...
Notebook, general purpose: VX Nano. The microscopic plug-and-forget receiver is great, gives you much better response than Bluetooth. The battery life is otherworldly. And it tracks on any surface, even my cat(!).
