Did some more compiling, 2.6.9-rc2 this time. Now k3b works and I've realised that my cdrecord package is broken, or the config is borked. I can blank cd's with:
cdrecord -v dev=/dev/hdc blank=fast but recording doesn't work even as root from a VT.
Oh, well, I'll just use k3b and see if cdrecord is updated sometimes soon. K3b seems to use mkisofs, cdrdao and growisofs for burning so at least I can burn, I'll just miss my burning script.
And yes, I did a reinstall on cdrecord 2.0+a38-1 , and a dpkg-reconfigure just to be on the safe side

As a sidenote, running lilo or shutdown doesn't work with 2.6.9-rc2, so it's 2.6.7 for now.