Ok, I gave it a fair shot and I like it but........
Wonderful thing about having two computers, you get to compare operating systems side by side. If you are immediately drawn to one or the other, you find out.
On the right, the home boy, Ubuntu Linux 9.10, sporting the preview version of the Gnome Shell. On the left various challengers including XP (he gets few calls these days).
Just installed a second drive on this second PC so fresh installs are the way to go. Xubuntu is first, I installed it and the little window size buttons and header bars did not appear or work. Gee, it worked before on this machine. The live-CD runs OK and I am moving windows around, but compared to the Gnome Shell it is extra work to get to stuff. Then another live-CD, Elive 2.0. This OS is a drooler, it is so good looking. Elive has compositing charm but no compositing. This means you can still run it on a low resource machine and get good performance. But wait, darn, I have a warning window that says ATI video cards are known to cause problems with certain drivers and may crash the system. It works but missing icons and quirky actions, drat that ATI. We'll have to try another video card and see how it goes. Elive 2.0 is still racing after the Mac type desktop but has the Linux toys, compared to Gnome Shell?
The Gnome Shell just sits there working with almost no effort (fewer mouse clicks). I don't have to set up shortcut icons and application launchers. I think the work flow is a little smoother. The big shock is accepting how it's setup, you know how Linux users are fiercely resistant to being told what to do and how to do it. The good thing is that so many other desktops exist. I hope if the Gnome Shell becomes the standard, that the windowing desktop folks are use to is not thrown away. Then you can put regular or decaf in the session selector when you log in.
What's strange is I like the Gnome Shell over the what we all are used to in windowed desktops. It reminds me of Konqueror, the file manager/browser/viewer that could do so much and was under appreciated, basically the only thing I liked about KDE. And also a little bit of Matisse desktop, which was mostly in Mandriva Linux. To me, this is what a PC is all about the file manager. Having access to my files is the most important thing, then the program menus. So how to get there has to be short with fewer distractions. I didn't like compositing because you had to "find" a working setup yourself.
Linux is wonderful with all the choice, but the selfish arrogance of some vocal users hampers wider acceptance. A better solution would be configuration recipes posted that other users could immediately appropriate. This way the folks with simple needs can better find their way and the boasters can still show off with gusto. Science is about repeatable results, not just being the first and the most extreme. Community is about forging the way for others also, else wise you are adrift on your own iceberg (global warming anyone?).
There is the glitz of all kinds or screen manipulation, multi-touch, immersion 3D........... then there is making present technology and user habits more efficient by changing the beginning premise. You can do this in Linux. KDE almost did this and you have to like the way they made it customizable. But KDE is too fidgety. Everytime the cursor passes over something there is possibility for unwanted change. Gnome Shell is more static feels more stable. When I click, I know what to expect. I found the same thing when comparing KDE's BasKet Note Pads to KeepNote. They both allow text and pictures, but BasKet Note Pads requires care because things move and float. So a program can run stable, but is it stable in the user's hands. If the program feels sure in the user's hand, they have confidence to use it more often.
Gnome Shell is cool but make it a standard "option".