Understanding before criticism: fink and Zoularis
I am an avid Linux and *BSD user who develops some open source software and I just bought an iBook which I love. Like every tool, you have to know how to use it. Most of the "missing" software the author complains about it easily installed via the wonderful Fink (http://fink.sourceforge.net) project. Fink gives you an apt-get system, precompiled packages, the ability to compile from source, and has a large number of Unix packages. I'm currently drawing diagrams for a project in X11 using Gimp, Dia, and XFig.
If you are a BSD Unix freak (unlike the fake Linux version of Unix that doesn't even require you to specify the directory when using find :-) then you might like the Zoularis (http://www.netbsd.org/zoularis/) project. Zoularis has quite a few packages available and works like the NetBSD pkgsrc (which is like FreeBSD and OpenBSD ports collection).
Finally, you can just download the developer tools from Apple. The developer tools not only come with all the GCC stuff, but it also comes with Project Builder and other nice tools. The free developer tools from Apple are better than most of the stuff you'd pay for from other companies.
Personally, I could care less if OS X is officially Unix. Linux isn't really Unix either, according to their own admissions. Unix is notorious for being inconsistent and poorly designed for usability. Guys like me and the author like Unix, but most people want a consistent easy to use system. Having to edit anything in /etc is not easy to use, but for some reason, Unix people believe that anyone can do it. Just because some can do it doesn't mean that they should have to do it.
Anyway, try out Fink and Zoularis and see if that makes it Unixish enough for you. Hell, I'm even running all my stuff on a separate X11 screen in WindowMaker. It's like I'm using my Linux box.