I have installed F13 beta (+updates). rd_NO_LUKS was added to the kernel line automatically. I have one (non root) partition that is LUKS encrypted, however, I still get a password prompt during boot.
Maybe during boot, but not in the dracut phase. Might be already in the real root from rc.sysinit. Fix your /etc/crypttab.
Ah... I hadn't modified the file myself, looks like anaconda did this during installation. Also, I was not aware of the dracut<->later boot phases or that partitons can be unlocked in both phases.