Over on the SFSFW Yahoo Group a discussion broke out about the nature of the Hrud (my fault as I suggested they might make an interesting adversary in Space Hulk).
Initially GW were going for the Space Skaven approach but have subsequently tried to move away from the fantasy in space idea (bit hard with Orks and Eldar methinks...) and recent mythos has been of a more insect-like race (albeit with similar tendencies to Skaven).
Anyhow the possibilities of the Hrud led me to writing up some rules for introducing them in Space Hulk and I've sent this off to Ragnarok for consideration. The main differences to the Genestealers is that due to the Hrud distortion field blips are not revealed on line of sight but have to be actively scanned at the cost of 1AP by a Terminator. They can also pass through occupied squares. Obviously I need some models and a copy of Space Hulk III to get the rules down pat but I think they'll prove a different challenge to the 'stealers and fun to play.