Leave it long (or however you like it!!)
If an employer is hiring based on hairstyles rather than legitimate job competencies... then you really don't want to work for such a bonehead employer!
+1
Ive cut my long hair off a number of times including one full shave, only to grow it back every single time. Long hair just seems to be part of who I am. My ponytail is currently only about 6 long and sometimes I trim it down to maybe 4 but thats about as short as I go these days.
If you like it, I say tie it back, be otherwise well groomed and go to your interviews with confidence. Ive certainly found a lot more acceptance to it than there was years ago.
Good luck with your decision.
