As someone who has run forums before (granted not one of this size) it is hard to give a certain group their own forum without knowing that there will be a lot of support for it already. From what I can tell, there is not enough discussion on here to warrant hockey having it's own forum and unless there is a large group of people that come out and say "I'd post in a hockey forum" it will be difficult to validate dedicating a forum to hockey.
Also, it seems to me that the staff of GopherHole is devoted to Basketball and Football (based on the Records and Recruiting databases). GopherHole is for profit and these are the sports that bring the most hits.