In part it feels weird because it doesn't seem justified. If sf reviewing were a salaried profession, there are a large number of people I'd put in the queue to be employed before myself. This is, clearly, not false modesty; there are a lot of good reviewers in this field, and to a fairly large extent I often write about books because other people aren't. If I could get anyone I wanted to write about anything I wanted, I doubt I'd personally write very much. (Convenient that I'm a reviews editor, you might say.)
In part it feels weird because, well, I'm just not used to it. This is not an enterprise with a large target audience. Shallow shiny commercial reviews are a possible exception, but I don't have much interest in either writing or reading those. So I've never expected to be paid for anything I write, and (review copies aside) the majority of places I've written reviews for--Foundation, Interzone, Vector, etc--don't pay. Even somewhere like The New York Review of Science Fiction only pays $10 a review.
I can't imagine not wanting to write for any of those places because of their pay rates or lack thereof. NYRSF is arguably the most respected venue for reviews in sf at the moment; getting a review in there means something. It's a similar story with the other three, although other factors come into play, as well. For some of the above, I write reviews because I want to support them, and I think I can do a decent job. For some of them, the editorial guidance they offer is crucial: I want feedback on my reviews; I want to get better. (There are also venues I don't desperately want to write for, despite the fact that they pay, for the converse reasons.) And then there are the reviews I write, as mentioned, just because other people haven't done so. That's the impetus behind blogging, after all, wanting to be part of the discussion.
At this point we come to Strange Horizons. Before last autumn's relaunch, the Strange Horizons reviews department bought and published one in-depth review a week. Since the relaunch, we've been publishing four reviews a week, and paying for as many as we can. We can't afford to pay for them all. The theoretical solution has been to have a cutoff point, with reviews of 500--750 words unpaid, and longer reviews paid. In practice, many people have been generous, and donated longer reviews.
It is, obviously, not an ideal situation. I try to rotate, but there are plenty of people I haven't been able to pay yet. The immediate alternatives are to pay an (even) smaller amount, but pay for every review, or to publish less reviews. Neither of those appeal to me, the first because it would be an empty gesture, and the second because for the reviews department to be what I want it to be, we need to be publishing more than four reviews a month. What I want it to be, of course, is a venue of the type I was discussing above: a place people want to support, a place people receive whuffie for being published in, and a place where people know their reviews will be well-edited. The long-term theory behind Strange Horizons, not just the reviews department, is surely to believe that it can develop a virtuous circle: that putting out good content will increase the audience, which will increase income during fund drives, which will enable the magazine to pay more for more things.
There are various failure points in this plan. An obvious one is if the editorial control sucks, but (equally obviously) I prefer to believe that the editorial control (in all departments) is actually pretty good. Another failure point, though, is that if it turns out that most people who write reviews aren't like me--and guess what? That one might be true. For starters, there are plenty of reviewers who are also writers, who review partly to earn a little bit of extra money, and who therefore won't want to review for Strange Horizons. This is not unreasonable. It would perhaps be possible to dismiss such people as mercenaries who don't really care about reviewing for itself, but given the large number of author-critics that sf has generated and continues to generate, such a reaction would more than likely be unfair.
So there we are: money makes things complicated. Big revelation. I suppose that if I were to really practise what I preach, I would donate anything I earn from reviewing to Strange Horizons, but when I can spend it on (say) this evening's theatre trip instead, I'm not quite that altruistic. It may feel a bit weird but, like everyone else, I'd prefer to be paid than not.