So, using the method below, I've started testing. A review of some sort should follow...
sudo add-apt-repository ppa:gwendal-lebihan-dev/cinnamon-stable
sudo apt-get update
sudo apt-get install cinnamon
UPDATE (several hours later):
So far, I'm happy enough with Cinnamon-2.0. It seems to run with a smaller footprint, more stability and more functionality and configuration options than you get with the latest Unity and Gnome-Shell.
I did get a few random lock-ups during early reckless tweaking, but I've seen no recurrences since I stopped messing around with extensions, desklets and applets (some of them still only properly tested with earlier versions of Cinnamon).
Now, after several hours of work, the impression I'm left with is all positive.
In terms of workflow, I did find myself missing a few features of Unity's Dash and HUD, but the old desktop metaphors still seem to work better for me overall. And though this might have more to do with my long term familiarity with those, I also think it has something to do with a general lack of maturity in the newer approaches to the desktop environment being worked on.
Its still early days, but if nothing major shows up, I could very easily stick with Cinnamon as the desktop option I choose most often at login - at least until the others grow up a bit.
NEXT UPDATE (... in the morning)
I think I'm changing my mind .. The new day has found me missing Unity's simplicity and that task orientated Dash and HUD.. Ah well, I'll decide later, but just now I felt crowded and in my own way - I'm writing this after logging back into Unity ... maybe for a long while...