Mac OS X's kernel (xnu) has been engineered in such a way that you shouldn't ever really need to recompile the kernel. You can dynamically load and unload kernel extensions whenever you wish. You can recompile your kernel if you really want, but it's probably more hassle than it's worth. Just wait for someone to bring out cd burning support. Apple is working on their own support, and I'm sure Roxio has demonstrated OS X-ized versions of Toast before, so that's in the pipeline too.
I'm not sure if cdrecord would work or not, due to underlying differences in the way hardware is accessed.