I've bought a MacBook Pro and I've been using it for more than a month. In the past 5 years, I've used nothing but Linux and AIX. I am a proponent of GNU/Linux, but I am not against commercial software by any means, mostly because I think that programmers should be compensated for their work. I'm *not* a programmer, although I do program in Fortran, it is purely for science and not is not "system" type programming. I see fortran coding more as using an application because it is such an easy language to use.
My setups: Linux SuSE 9.1 64 bit on SUN w1100z (an opteron chip.) I bought a LCD 15" screen with it for $300 dollars and I bought the DVD distro from a retailer so that install would be easy on me. Altogether I payed $1450 for this setup. Install was a piece of cake.
My OS X is on the 2.0 dual intel MacBook Pro. Install was done already. With discounts and Microsoft Office I payed $2800.
Anyhow, the first thing that I have noticed with Mac OS X is that I have a genuinely hard time reading all of the information that is on the screen. I can use the open-apple and (+) keys to increase the size of the screen but I can only do this for the main part of a screen. All of the tabs and menu items remain in fonts that I have a hard time with. I wear glasses, but my correction is 100% so that I can see like a normal person. I constantly have a hard time taking information from the screen as quickly as I can on my linux box. Part of this might be that the screen from my Linux box is easy to set up high. To do that without pluggin in a monitor to my Macbook, I'd also have to have the keyboard perched up high.
The next thing that I wanted to do was set up "the nirvana editor," NEDit, on my Mac OS X. It turns out that you cannot do that unless you want to be the first one to do it. The binaries available are for the power computers. I might take a crack at it when I have a day available. The problem is that I don't have a complete idea on how to port applications to OS X as I do with Linux. That is going to be a sore point for a while.
For the most part, I've noticed that things seem to open faster on my linux box and applications run faster. Also, I'm able to operate KDE and applications within KDE without using my mouse very much. That isn't the case with OS X. I've often reached for the number pad on my Macbook just to remember that there are many fewer keys on this computer than on my linux computer.
The big plus on the MAC OSX is oddly enough the Microsoft product on it, Office. I'm not a big fan, but I have to use it for work. However, they have done a good job with porting their applications to OS X and it has many features that I haven't been able to find in Open Office. Open Office is much faster though.
So a month and a half or so in, I'd have to say that KDE/Linux is the winner over Mac OS X. I think that when I get more comfortable with OS X it may turn out to be a tie.
The reason computer chips are so small is computers don't eat much.