1) Kevin Tong's poster for Metropolis uses greyscale and ominous red highlighting to hint at the story within: the transformation of robot to Maria and back is hinted at in the main image, and vignettes convey both the industrial hell of the undercity and the isolation of the towering homes of the elite. I think it says a lot and does so very economically, and it has my vote.
2) Richard Wagner's illustration for "The Angel at the Heart of the Rain", from Interzone. The figure of the angel itself is pretty striking: Asian angels are rare in art, so the viewer immediately has to question why this is, and why it matters. Yet the bystander, perhaps a commuter waiting for a bus, is looking the other way as far as we can tell; for him or her it's a perfectly normal part of the world. If, that is, the angel is visible at all from the commuter's viewpoint; I felt not entirely happy with the perspective between the angel's plinth and the bus shelter - the visual cues are a bit confusing as to their relative scale, height and distance, and this marked it down for me.
3) Finally, Joey Hi-Fi's cover for Tony Ballantyne's Dream London. Like Kevin Tong's Metropolis poster, greyscale with red highlights; a red-coated man on a wooden jetty looks away from us, across the Thames to a jumble of tall buildings from London and elsewhere, some of which are ornamented by ominous red tentacular things (plants? dragons? Can't really see clearly). I am sure that there is good reason for jamming all these buildings together away from their geographical homes, but it jars my sense of location; the human figure seems a bit clichéd; and I'm putting this last. I note also that reviews suggest that in the book, London is reverting in some ways to the Victorian era; this is not really signalled by the cover, but I think we should judge it in itself as a work of art.
Non-fiction coming soon.