...I've written a little review

Kubuntu has a bit of history here, it's always played second-fiddle to GNOME-based Ubuntu, which, whilst not a bad thing in itself, is hell when you've got bugs to patch and tools to implement.

Anyway;

THE GOOD



Networking

In Kubuntu 9.04, myself and many others could not connect to WPA2 wireless networks with KNetworkManager. Thankfully this problem is resolved in 9.10's more modern version, which is perhaps one of the most fastest loading networking clients I've seen (and has, apparently, been largely rewritten)


KWin

In KDE 4.2, KWin's special effects was a resource hog, guaranteed to kill anything I was doing on the machine in question. Here, KWin can give me a modern UI without making my cooling fans believe they are aircraft engines.

Power management

Many people (again, myself included) had problems with the kernals used in 8.10 and 9.04 when it came to power management, suspending/hibernation and shutdown. They would not work, no system could read my battery level, the system would only crash instead of suspending, and I had to perform what the manual refers to as an 'Emergency shutdown' to turn the damn machine off; now it works fine by itself, and I can make use of KDE's PowerDevil

VLC

As is customary, every package gets updated for a new version; VLC's latest release available in 9.10 ends the age old problem of videos and controls being in separate windows! ...sorry, I like VLC, so I thought it worth a mention...

Amarok
Amarok, like VLC, is updated. and just like VLC, it rocks! The widgets are now remembered and the controls don't look buggy any-more. Also, the lyrics widget has been replaced.

Speed

Even with the introduction of Akonadi Server, the system is still faster then 4.2...much, MUCH faster!

Appearance

With the introduction of the new default theme; 'Air' things look a lot better, also, the default login window has been brought up to 21st century standards.

THE BAD

Package-management

The much talked-about Ubuntu Software Center (also known as the AppCenter) is not installed by default in Kubuntu. Rather, a more updated KPackageKit is active. This version includes a few enhancements, particularly over the UI; it's inabilty to install software sanely is still very much insane (remove-download-install over Synaptic's download-remove-install) which can cause some headaches if you need another networking client.

Kopete

Kopete is not devoid of changes, the annoying automatic-insertion-of-emoticons-into-hyperlinks has been resolved. However, most of the plugins are still as buggy as ever. The translate plugin refuses to work, for instance...hopefully this will be resolved in time...


Live-mode

Attempting to do a boot into a LiveCD (then LiveDVD, then LiveUSB...) mode to install failed. My own machine would just turn off without warning.
I would advise anyone having a similar problem to upgrade via 9.04 (or wait for a few days after release to get those bugs sorted out)

You wrote:

"Networking

In Kubuntu 9.04, myself and many others could not connect to WPA2 wireless networks with KNetworkManager. Thankfully this problem is resolved in 9.10's more modern version, which is perhaps one of the most fastest loading networking clients I've seen (and has, apparently, been largely rewritten)"

I'm running Kubuntu 9.10 Beta and still have grayed out wireless in the manage connections with all the updates to the hour. How can you get wireless when I had it before on 9.04 but lost it with 9.10? I also got the package for the widget for kde networking and it did not show up in my task bar. I'm confused. Bob

@bobcollard: Remove any network manager plasmoid you have added and run "knetworkmanager"

The KNetworkManager used in 9.04 (along with it's own plasmaoid) was rather horrible, in my experience. How are you running 9.10? upgrade or install?

I've kept up by using new live CDs and restoring after installing from backups. (External USB Drive) The funny thing is I have never had any problems with 9.04, networking or otherwise, it was completely stable, until KDE 3.4 came out. My original Live CD has KDE 3.2.2 When I decided to go with 9.10 I bought an ether net cable and hooked my laptop hard wired into my router. Now I have two desktops, not much fun in that. I tried WICD and it will not find my router, it's a Cisco Linksys G. I guess I'll wait it out and see how 9.10 does after the smoke dies down. I do like the other things 9.10 has that 9.04 did not.

Just a side note;

During my time with 9.04, I removed KNetworkManager and installed WICD. The removal of KNetworkManager also removed the plasmaoid of the same name. Upgrading seems to of shut down WICD and replaced KNetworkManager