I just installed Ubuntu 10.04 (clean install from 9.04) and was dazzled with its performance & looks. The installation process is simpler than simple and everything just works. Best experience with Ubuntu so far!
The only issue I have encountered so far is the negative color/hue balance while playing videos. I use Totem Movie Player with totem-xine as the backend for playing videos. However the hue balance was not correct even when I used MPlayer or VLC.
I have described the simple resolution to resolve this issue below:
Type Alt-F2, launch gstreamer-properties -> Video Tab -> Default Output -> Change “Autodetect” to “X Window System (No Xv) ” option.
That’s it and it just works! Hope it helps. 
System Configuration: Dell Inspiron 1520, Intel(R) Core(TM)2Duo Processor T5250, NVIDIA(R) GeForce(TM) 8400M GS with 128MB GDDR2 dedicated graphic memory, Ubuntu 10.04, kernel – 2.6.32-22-generic
