Upgraded from Ubuntu 8.04 to 9.04 (Jaunty) beta over the weekend. It had to be a two-step process because first I had to upgrade to 8.10 (Intrepid). All that patience paid off well when I saw the result. No sound driver issues, and the machine’s nVidia card was detected without any hassle (a big relief from the woes of 8.04 I think).