i have been using Ubuntu on and off for awhile now, but just today i got in the mail the free Kubuntu CD's i ordered for free. its basically ubutnu 6.06 with the KDE desktop, but it is a lot nicer. so far, in the first few minutes here, im pretty impressed.
it even supports my atheros wireless card out of the box. takes some configuration with my last install of ubuntu (hoary hedgehog, not the latest version build)
also, some toshiba laptops allow you to scroll with the edges of the touch pad via toshiba's alps touch pad drivers. kubuntu also has that built in.
just using the live version now, but so far i can say this, every version of ubuntu/kubuntu gets better and better!