Do a search for "Bochet" ... there are a few threads showing different levels of caramelized honey.
Some people take it to a burnt level, others simply brown it a bit. It is supposed to give a more marshmallowy flavor to the honey.
I have a 5 gallon batch that is aging - I think I might have taken it a little far on the burnt side. I'd prefer, in retrospect, for a nice caramel color without going towards black.
Also, be forewarned that it can be obnoxious to heat up. It bubbles very high. In a 5 gallon pot, I could only keep it about 1/3 full before I started heating it ... it bubbles up a lot. Oh, and bees are attracted to boiling honey.