Inkworks has updated their Firefly cards page with new pictures of the case loader "Outlaws" card, one of the 6 "Battle of Serenity" cards, and the "Firefly Forever" limited edition uncut sheets (pictured). Cool funkiness!
Current best guess as to release date is May 17, according to Inkworks, "to spread out the upcoming Inkworks products." Also, check back for an announcement about the Firefly promo cards I've been giving out. They're about to get a lot more frequent, and there's more free stuff coming.