For many years Gentoo has been my favorite Linux distro and it still is. I used Redhat, Slackware and Fedora for a few years before that. Just installing Gentoo is such a learning experience. Although installing a software is as simple as doing "emerge X", configuring it is a bit more involved and requires you to dig up config files and editing them. No fancy GUI to help you. Which is the best part about it. I can learn how things work in Linux. Another reason I preferred having Gentoo over other distros is because all the packages are compiled for my machine. Which means all the executables make the best use of all the instructions and features of my processor and what not. But the main reason I use Gentoo is because I can compile the Linux kernel to my taste. Tweaking every bit and compiling only the drivers that I need. I almost never compile anything as a module. Everything is in the bzImage. All these tweaking always made my computer run super fast.
While all this is good and well, I always felt a lack of proper integration of various pieces in Gentoo. To get any kind of eye candy (pre KDE 4.3 days), I had to install a compositing window manager (also known by various other names such as beryl, compiz and compiz-fusions which were forks of one another and such), and a window decorator such as emerald. Then had to configure various animations in compiz and install proper themes for emerald. At the end replace KWin with compiz. All this was tricky and time consuming. I love learning how things work internally but this is getting to be a bit too much. Why do I have to invest so much time to just get the fancy animations and eye candy? I was also noticing something else. The computers are becoming faster and faster and the difference of performance between Gentoo and other distros is becoming smaller and smaller, to the point that all the tweaking is not giving me any advantage.
Moreover I now own a core i7 laptop. It is so extremely fast that nothing really matters anymore. I have been watching Ubuntu for a while and looking forward to their new release -- Lucid Lynx. They are claiming fast boot times and the UI looks really nice too. I decided to give it a try. Since I am a KDE guy and never really liked Gnome, I went with Kubuntu. I have to say it is really good! The installation process, installing packages etc was a breeze. And even better was that the defaults that these packages come with is very good. For example in Gentoo I would have to configure the global USE flag and package level USE flags to get the right stuff (like encoders/decoder for mplayer etc).
It is not to say that the process was not without hiccups. I initially used i386 iso and I started seeing oom-killer kill ureadahead (which makes booting so fast in kubuntu) and plymouth (the boot splash). That was not nice. I Googled about this issue and found nothing. I had a hunch that it could be because of 32-bit kernels having trouble addressing memory beyond 1GB (the low and high mem issue). So I decided to go with 64-bit iso and the problem went away :). Now I have a few more issues to resolve before I am completely happy. For example installing proprietary nvidia drivers made me lose the splash screen which I loved. The integrated mic is not working for some reason. Could it be pulse issue? I have to fix all these minor things, but for now I am a happy camper :).