I looked at Hyde, Cactus and Pelican, but confess I can't recall what I didn't like about the first two. Nothing seems obviously wrong with them. Maybe they looked unmaintained or not as mature as Jekyll, although Cactus has a bunch of recent commits so that doesn't seem right. With Pelican I was scared off when I saw the license (Affero GPL, which forces you to provide source if you use the code on a live site, or something like that).
Sorry this isn't a more useful comparison. I wanted to find a good-enough SSG quickly, so my search was pretty shallow.