Spent the weekend offline cleaning the house and doing a fresh install of Fedora 2. I was not able to get any of the Fedora 2.6 kernel rpms to work with my upgraded system so I thought a freshinstall would solve the problem. Turned out the problem was more sinister than that. Turns out that the 2.6 kernel is not able to mount any of the partitions on my old disk (standard ext3) instead I needed to switch to using my new disk. With the new disk everything works like a charm, but if I try to mount one of the partitions from the old disk I get a message saying that they are not valid blockdevices. Tried booting with my Java Desktop Live CD and it turns out that this is able to mount the partitions just as fine as Fedora 1 could. So there is definetly something strange with the 2.6 kernel in this regard.
With this upgrade I am also using ALSA now, which was part of the reason I did it, so I could help debug the ALSA mixing issue people report. Of course for me it seems ALSA mixing works perfectly….