Started my first mystery KAL this weekend with the swatch from the Goddess Knits Mystery Shawl group on Ravelry and Yahoo. It looks to be an interesting project.
From the various hints I've gotten reading the posts in the Ravelry group, it sounds as though it will be done in the round, which should prove interesting. I didn't care for the look of the fabric in the swatch when I did it on US 5's, so I dropped it down to size 4's (seen in the above swatch). I still think it's a little sloppy looking, but then I'm not an experienced lace knitter, and I'd really hate to have to drop to 3's.