For those who haven't heard (i.e. don't read /.) Linus Torvalds has recently blasted Gnome in favor of KDE. While the /. note is overly concise, the actual thread is pretty interesting (Linus' comments: , ; Gnome's responses: , , ). Part of the big rivalry between KDE and Gnome has always been centered around questions of design which invariably are tied to questions of user audience.
KDE says users must be able to configure everything (a side effect of targeting hackers who like to have absolute control no matter what the cost), whereas Gnome says things should just work (with the side effect of removing functionality/configurability). The designer in me says those aren't mutually exclusive ideals, but it does raise a set of interesting questions and some interesting problems for open-source mostly centering around the fact that hackers are rarely good interface designers.
Which, given their history makes sense— if you're writing a program or library to automate some set of tasks (where "you" can be a specific individual or some cadre of individuals), naturally you're going to have it abstract away the things you personally want abstracted away (if you abstract nothing away then what are you doing?), and leave in the widgets you want to play with (if you abstract everything away then how can you adapt to novel situations?).
The problem is, most hackers are designing for themselves, i.e. for other hackers. The area where open-source and linux are historically weak are "applications" i.e. the huge, pretty, GUI programs users think about when they think about their computer. Once you step out of the world of small, sleek, commandline programs you loose most of your assumptions about how to design an interface and how users are going to expect your program to work. With that reality, it makes sense to take a Gnomish point of view; things should just work. But we run into the issue that not all users are the same, and not all situations are the same, and if your program can't be adapted (read: configured) to fit those contexts then it will be discarded (or at least it should be, but then witness any IT department of long standing).
Me? I tried Gnome back in the day and it did not "just work". KDE was large and cumbersome and klunky, but at least I could make it do what I wanted to (witness the same reason why I learned vi instead of emacs). Down at the CAT on their linux machines they use CentOS which in turn uses Gnome. From the looks of it Gnome has grown remarkably from its broken upbringing towards its ideals. It's still not perfect, it's not even the best of alternatives, but it's certainly serviceable. Then again, CentOS's Gnome is different from just standard Gnome (which I've also run into recently and it still has a number of the problems it used to).
So what window managers do I like? Well if I'm bashing around on the commandline—which I almost always am when I'm on linux—then I prefer some of the hyperminimalist ones like ion. For more of a desktop experience, someplace I can feel comfortable and at home with rather than merely being productive, I'm a MacOSX fan. Of all the *nix window managers I've seen it offers by far the most consistent and well integrated GUI I've seen. It's not perfect of course, there are a few places where the world of Unix and the world of MacClassic don't mesh so well, but it beats the pants off anything else.