Default [Q] Phone stuck on CyanogenMod logo after update despite correct boot image flash.

I guess the title says it all. I've wiped the cache from fastboot as well. Done the whole thing twice, in the order of factory reset, wiping the cache, flashing the boot image, flashing the ROM. Still stuck on the CyanogenMod logo going round and round and round. :/
Side note: this might be stupid to ask, but is it possible to flash a new ROM in recovery without factory reset?