I've used windows for quite some time, I still run it on my main PC at home and run XP Tablet Edition on my laptop (tablet pc).  I also am quite familiar with Linux and have been using it for several years.

Suprisingly, I haven't really used a Mac until now.  Though its built on unix, it is still quite a change.  The whole mindset between Ubuntu (now my favorite distribution of Linux) and OS-X is different.  Although Ubuntu has brought a lot of simplicity to Linux by trying to unify many parts of Linux that previously did not work well together, it is not simplified as much as Mac OS-X.  I can see that being a blessing and a curse.  I think it's clear to see how a simplifying interfaces and applications helps the user out by not showing them too many screens that they don't know about.

Ok, but for a so called "power user" like myself, this is not the best for me.  Ubuntu (Gnome, etc...) has tons of possibilities for customization.  Everything seems to be "clickable" and has a menu to go with it.  Clicking any icon or panel will activate something and right clicking anything will activate a context menu which will allow customizations or settings.  Although some things take some work to get them running, sometimes finding the right program takes some work.

I'm going to give an example that spans across Windows, OS-X, and Ubuntu.  This is something a "power user" would do to customize their computing experience with a Logitech MX Revolution mouse:

Windows XP: Installed the drivers to set up the mouse.  I realized it didn't have a middle mouse button by default, but it does have a useless (to me) search button.  I knew I wanted to remap that to a middle mouse button.  That took some google searching but eventually I found that I could edit an xml file somewhere in the user Application Data folder (well buried).  The auto-switching between regular scrolling and hyper scrolling is well supported by the Logitech drivers, so that just worked fine.

Ubuntu: Mouse works on installation, but only two or three buttons are really working.  I have to do more google searching to finally find a program called Btnx.  This program basically allows me to capture all my mouse key inputs (it's written to capture and set up any mouse you want).  I can then set any button to do anything I want.  It's the epitome of customization.  I could also set up the hyper-scrolling here and set up how it works just as well as the Logitech drivers in windows, but in the end, I'd rather use Btnx than the Logitech drivers.

Mac OS-X: Mouse works out the gate, but doesn't have the forward/back buttons working how I want them to.  I downloaded the Logitech drivers for Mac, but they are quite inferior compared to the windows drivers.  I could not customize the buttons how I wanted to and I was still without a middle mouse button.  I finally found a program called SteerMouse which allows me to map all of my buttons (it doesn't have to do the capturing part of Btnx).  It does not allow me to do much customization for the hyperscrolling, but it does support some.  Also the mouse speed I was never able to get quite perfect.  OS-X doesn't allow you to turn off or adjust mouse acceleration (only speed) by itself, so I found another small program to do that called iMouseFix.

Conclusion: Logitech supports windows, so I would expect the drivers to work well there, but often customizations in windows involve finding a custom program or find an obscure registry entry or xml file (like this time).  Ubuntu will let you customize the crap out of anything, but unfortunately how do you find a program called "Btnx".  That program is so poorly named.  Also it could definitely be confusing to use.  As for OS-X, they don't give me nearly the amount of customization I need by itself, but then I was able to find a program that provided a decent amount of customization, but here's the problem, the program costs $15.  In Ubuntu, nearly everything is free (as in beer; gratis) and a large amount of that is free (as in speech; libre).  There's another example I have of OS-X where the right program for the job is not a free one.

I bought an Infiniti G35 with the Tech, Nav, and Premium packages.  It's blue slate (dark blue) with a wheat (tan) interior.  Roughly everything about it is awesome--navigation, bluetooth phone, xenon lights, heated seats, backup camera, adaptive cruise control, etc...  Main low points are the voice command list has been shortened since 2007 models, it doesn't have a blind spot sensor like Volvos, and the main low point is probably paying for it.