I had been hearing some buzz around KDE over the past few months. People saying how much it has improved and praising the features of the advanced desktop environment. My thoughts were that eye candy is fun, and plasma widgets may be cool, but I was curious whether I could be as productive (or maybe more) in KDE, and I knew that figuring that out would require me setting down and actually trying it hands on for a little while. 
Since I was in an experimental mood I went with a fresh install of Kubuntu 9.10 alpha 4, and it installed in about 30 min with no problem. My initial impression is very positive - plasma widgets are cool! Lots of cool functionality out of the box, and it looks pretty too! Things like WiFi and desktop effects were a simple matter of turning on.
Firefox isn’t included, which just feels weird to me, but Arora seems promising. It even prompted me to install the flash plugin when I started it up, but though the install appeared successful flash didn’t work. The file manager, Dolphin, seems sweet! more features and options than Nautilus by far. This is a big plus for KDE, though you could use dolphin in Gnome. The usability of something this fundamental is hard to determine in such a short time, so I don’t want to make to strong of judgments to soon, but so far I feel confident that Dolphin would enhance my productivity. Split views, tabs, columns,previews, zoom slider - nice!
I spend a lot of time in a text-editor. I have come to love Gedit, Gnome’s default editor, for its lightweight and feature full (via plugins) nature. Kate is the corresponding application is KDE. My initial impression is that it has some features I have missed in Gedit - split view is the one that really stands out, but it also seems to be missing some pieces I would like to see. And after the impressive GUI of Dolphin I fell let down by Kate’s lackluster interface, but it is very similar to Gedit, so no real complaint.
After messing with KDE for a couple weeks some of the sparkle that initially impressed me has started to fade. It has been dulled by a desktop environment that is different enough from Gnome to really confuse and lose me at times. It is hard for me to tell how much of this is just unintuitive and how much is me being mentally trained to do things a certain way. Various things just don’t work (of course this could be due to the fact that I am using a development build…) , and overall the desktop just feels less snappy and responsive than I am used to in Gnome.