Thanks to Tim Holman’s neat bar graph we can tell at a glance which fantasy art clichés appeared most often on book covers in 2008:
[The] most commonly seen element appearing on fantasy books published last year was, it seems, the sword. Closely followed by glowy magic, castles, and dragons. I suspect a few covers contained all these elements. Meanwhile, fans of unicorns, maps, and stilettos had a disappointing year, and perhaps were lost to other genres.
[Thanks to Andrew Porter for the link.]