For all the people complaining about no Windows 7 vs. Ubuntu 10.04 comparisons as if someone is trying to hide something on purpose. Did you hear about a thing called Google?
A simple search for "Windows 7 vs. Ubuntu 10.04" brings about a wealth of information and comparisons. Here's some:
http://www.phoronix.com/scan.php?page=article&item=linux_windows_part1&num=1
http://www.omgubuntu.co.uk/2010/05/boot-race-video-ubuntu-1004-vs-windows.html
The fact is that Ubuntu 10.04 trades blows with windows 7 and the boot of ubuntu 10.04 is faster than win7.
As one of the posters noted here, windows gets so ridiculously slow overtime due to it's tendency of being like a garbage bin, notably after you install/uninstall programs. This is one of the reasons why I left windows something like 7 years ago after using windows for something like 10 years.
What I can tell you is that I'm very pleased with Kubuntu. I'm running the 7.04 version over an old machine by now for more than 3 years without reinstalling and the thing just works like a beast with the same speed launching the programs and everything just like I installed it yesterday.
Who has spare strengths, time and nerves to reinstall windows every 6 month with all the custom setting's and all the programs again and again and again just so you keep your computer usable and working in full speed and not wasting your time?
I keep a dual boot win XP for games and maybe a win only application I need to run sometimes and that's just it.
When I buy my next rig I just load it with Kubuntu 10.04 LTS, set it up the way I want and forget about it for the next 3 years. Remember there are a lot of people that just don't have the spare time to babysit the robot all the time, folks like students, busy business people...etc.
Anyway I like kubuntu very much and am sure to upgrade to it the next time. Thanks to all the developers and people that put their precious time and effort to develop this FREE open source marvel that people can use.