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But, in my experience at any rate, it's also a strategy which eventually pays off in terms of:
a) the number of search-engine-independent repeat visitors you get once your brand is out there in the public sphere and well-known
b) how often your website gets mentioned in topic-relevant articles in the mainstream press as a champion of its niche
c) how both a) and b) enable you to grow a loyal readership who will then spread the word about your publication not only by word-of-mouth but also by email, IM, social bookmarking, social networks etc. (How many shopping portals can say as much?)
d) Carefully crafted articles can be excellent link-bait
Note that you can stretch the magazine paradigm quite far - your website can have aspects of an offline magazine without simply consisting of a collection of pages with articles and adverts.
WebmasterWorld for instance is self-evidently a forum. But it starts with a contents page, features readers' questions, readers' anecdotes, (collaborative) editorial pieces commenting on industry news and has an archive of articles. These are all magazine-type elements.