I don't think there is a way yet, not without starting your own "private" magazine. But it would make sense to have a section in your user profile where you enter a list of tags you want to follow, just as there is a way of adding a list of users that you follow.
Although... it occurs to me... I'm not sure how kbin actually uses that list of users you follow. But wherever/however that is, it would make sense to add followed hashtags also.