@atom0s: sure, I mainly use it for a more fine-grained matching on instructions with wildcard registers, for example FF D0 (call eax), for call reg you need to match FF D?, so without nibbles you would match on FF and this also matches a lot of other shit (invalid instructions, inc [reg], call [] etc). I agree that in signature matching it isn't quite useful, but if you need to find the next 'call reg' in a reliable way you need nibble matching. Same applies to 'push reg'.
Obviously if you feel it's a bloat you shouldn't use it
I just commented so other people don't have to implement it themselves.
Greetings