(As of 2010-01)
After 4 years of Ubuntu as my main OS, I've gotten fed up and upgraded to Windows 7. Looks like I'm not the only one: https://www.google.com/trends?q=ubuntu%2Cwindows+7

(As of 2009-05)
Ubuntu 9.04
  Repositories:
  Main, Universe, Restricted, Multiverse enabled
  Security, Updates, Backports enabled (not using Proposed anymore)
  PPAs for FreeNX, OpenOffice, aMule, Maxima, GNOME-Colors, SuperCollider, Pidgin, ...
  Repositories for VirtualBox, Wine, Partner, Medibuntu, ...

Dell Inspiron 8600
  Intel(R) Pentium(R) M processor 2.00GHz
  nVIDIA GeForce FX Go5200 64M
  15.4" WSXGA+ (1680x1050 widescreen)
  Intel® PRO/Wireless 2915ABG

Dell Optiplex GX260
  Intel(R) Pentium(R) 4 CPU 2.40GHz
  Intel 82845G/GL[Brookdale-G]/GE Chipset

http://www.endolith.com
http://brainstorm.ubuntu.com/contributor/Endolith/