I'm staying with Gnome 2.xx on my major stuff right now, but I'm not sure what direction I'll take it if they don't get their act together and forget this Gnome 3 business. I might even have to consider KDE, though I dislike it. Unity is useless. LDXE, XFCE and some of the other lightweight solutions just aren't feature-rich enough to be comfortable in a production environment. For average desktop use, however, I find that JWM as implemented in Puppy is totally decent.
I also tried to give Unity a decent go, and it proved too difficult to manage through the menus. But falling back to Gnome classic (I think?) is fine.
And my bride would short-circuit trying to learn yet again where to find her files.
My wife is a first grade teacher and none too computer savvy, but she now prefers a gnome desktop over windows. At first she complained because it looked different, but after I told her it was either learn a few new menus or pay $100 for a windows license, she wised up. A couple of days of her asking "how do I..." or "where is..." and she was on her way.
The gnome 2 layout is simple and intuitive in my opinion, and that's vital for a beginner. You need an interface that gives you what you want and then gets out of the way. Same for advanced users, for that matter. What you don't need is a bunch of bubbly [censored].
The GNOME folks has reworked their desktop in order to address tablets and touch screens. I understand that the KDE desktop will remain as it is and a branch of KDE will be designed specifically for mobile devices.
Debian stable will be supporting Gnome 2 for a number of years as it is the one included in Squeeze. There is also a new fork of Gnome 2 called "Mate". The dev's are still getting their stuff together for it but it ought to pick up some steam in the coming years, like the Trinity fork of KDE 3.x is doing gradually.