Okay, I've only used KDE 4.1 for a couple of days and I have a little more to report. The first thing to say that this is my favorite KDE "straight out of the box" that I've encountered so far in my limited experience. Aesthetically, this couldn't be better - I think it's much sleeker than Gnome (will see what Gnome 3.0 brings) and rivals the design of Mac OS X (sorry - prejudice aside, Vista's not in the running here!). The eye candy is abundant, but not overdone. The last thing to say about the "look" factor is that in all my years as a computer end-user, I have never just wanted to sit there and admire the desktop, especially without changing the default wallpaper. I can't help it - I'm posting another screenshot:

So let's consider it a settled point that KDE 4.1 is very pretty.

There are, though, some issues I've encountered. I've always found KDE to be a bit buggy, and this one seems to be no exception:

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