The good news: I now have sound support. The built-in YMF-744B audio controller (snd-ymfpci) works out of the box with Fedora Core 3, at least for basic alerts (haven't tried any music yet, although I'll have a stab at playing DVDs once I have time to install VideoLAN).
This time around, however, Wi-Fi setup took a little more time: around a couple of minutes. The trick was to remove all the previous network devices using the Gnome network settings applet and re-add the wireless interface set to "Auto".
As to general impressions, it's virtually identical to Test 3 (only a few packages have been updated that I've noticed). Of course it doesn't have the current Gnome bleeding edge release (it's the still-fresh-and-slightly-quirky 2.8), but it feels every bit as polished as the other Fedora incarnations, has everything I need and is organized the way I'm used to. Can't beat that, and I'll be upgrading all my boxes to it as time permits.