It seems that Kubuntu comes with a default KDE4. Maybe there'll be some "Kubuntu branding" later, but until now the desktop looks like the screenshots I know from other KDE4 distros:
I don't know whether it's KDE4 or the fact it's installed in a VM, but Kubuntu acts rather slow compared to Ubuntus Gnome desktop. So I concentrated on Ubuntu.
The boot screen looks familiar...
...but the default Gnome GDM and desktop theme changed a bit and I think they're doing better with every new release. OK, this is just eyecandy. What stroke my eyes was the shutdown screen, when I read:
* Stopping firewall: ufw...
Firewall? Ubuntu? They never had a default firewall shipping with any of the former releases and it is always one of the first things I install. Great news! "ufw" stands for "Uncomplicated Firewall" and looking at the commands that seems to be true. I didn't find a GUI to configure it but I don't think you'll need one:
I like that! I guess you have to go into detail if you want to tweak it as you want, but as a start it seems OK. I always considered it as one of Ubuntu's few weaknesses to not install a firewall as default. I found this about ufw in Ubuntu's wiki.
Hardy will come with the new Firefox 3 as default browser. The final release of Firefox 3 will be in June so I guess we will get a beta of it with Ubuntu 8.04 at first. By the time of writing it's beta 5.
I run this browser with Windows Vista and so far no complaints.
This was just a very quick and brief first impression of Ubuntu's upcoming release. If you really want to test it, download and install the beta! But be careful - it's beta... If you like some more detailed testing infos (and speak German), you might want to take a look at Suzan's Ubuntu blog.