Well I just had a long, fancy review almost ready and dropped a pair of zip disks on my keyboard. I dunno how it managed to kill X???
Anyhow, to summerize:
SYSTEM WIDE MOUSE GESTURES!!!!! All I can say is wow!
The whole thing does feel much faster now.
Konqueror doesn't do as much weirdness displaying pages and is
way faster. They also messed with the sidebar tab in the filemanager section (big improvement IMO). It also hasn't segfaulted yet, which Konq did in 3.1 and 3.0 all the time.
PlastiK, the default theme, looks really good. Kind of like Windows XP if it wasn't so ugly (colors are less gaudy, "3d" bits aren't as deep, etc).
Kopete is pretty nice (though still not up to gaim standards).
The graphical font installation gives you more control over what's happening.
Oh, KDE finally got a nice integrated real time resolution/refresh rate picker (like windows has had for ages) in KControl.
You can make the kicker transparent now.
Here's a screen grab of PlastiK (though I am using the Aqua-fusion color scheme, it's a bit better than the default):
EDIT: Oh yeah, and small things (like the bouncy icon next to the cursor, changeable kde startup screens, animated color change buttons in PlastiK) make it just look and feel more thoroughly thought out.