Looks like Microdia beat Samsung to be the first to release a 64GB CF card. Samsung announced that they were coming out with 64GB CF cards back in September 2006. I've been reading about a June 2008 release date for the 64GB cards but have seen nothing to date. Found a couple of articles on the Microdia card with 300x write-speed (sweet!):
PMA Australia 2008: sneak peek > Features > PC Authority
Microdia Launches 64GB Compact Flash Card | Gadget Lab from Wired.com
Microdia beats Samsung to market with world's first 64GB CF card - Engadget
Maybe this is the reason for the recent price drops for the 32GB CF cards.
-LocutusBorgMan