Just 
yesterday, Canonical released one of the most important Ubuntu versions of its history: “Natty Narwhal”. The most famous Linux based desktop officially did away with the Gnome shell and replaced it with the Gnome based Unity shell (wikipedia to the rescue).
There was a time (see here) that I really wanted to like KDE 4 as opposed to Gnome. I only reverted back to Gnome, because KDE was slower than a pair of mocassins in a pot of molasses. So, yesterday, I started the regular upgrade process: The upgrade to Unity/Narwhal went fairly smooth and when the much touted shell finally showed up properly, I was fairly impressed. While toy-ish, the window handling appears fairly intuitive (“Mac-like”) and the general layout looks, well, clean. However, it’s buggy and it’s slow, with disk-activity and processor activity spiking out of control without any particular reason.
Returning back to Kubuntu, (you know, all things KDE), I was pleasantly surprised to find out it that is a lot more stable than I’ve seen almost 1 year ago. Heck, it’s even usable. Kubuntu or Ubuntu? Kubuntu, for now. Maybe in another year, I’ll be looking at Unity as my default desktop environment, but as far as it looks like right now, I won’t be looking at Unity for a while.
05/05/2011: It looks like my laptop (equiped with an Intel 9xx GPU) wasn’t the only one with sudden freezes: it seems to have been fixed, right a couple of days ago.
Same here, it looks like there will be no GNOME 3 or Unity for me for a long time to come. They are both completely broken currently and will need a lot of work to get all the functionality of GNOME 2 back and even lonfer time to get to the level of KDE. I’ve just switched to openSUSE with KDE 4.6 now and it’s spectacular.