After what seems an interminably long gestation period, Digital Spy has confirmed that Stephen Fry is teaming up with Mark Carwardine for a TV series of Last Chance To See!

Iostar, the media group set up by former Hallmark executive Mark Grenside, has showcased its first productions at the MiPTV festival in Cannes, including three BBC documentaries fronted by Stephen Fry.

Stephen Fry in America is a five-part 'road trip' which sees Fry driving round the US in a London taxi and Last Chance to See sees him team up with zoologist Mark Carwardine to track down species facing extinction.
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The programmes are believed to have been produced in association with Fry's own production company Sprout. Fry and his production partner Gina Carter are registered to attend the Cannes event.
I'll post more as further information becomes available.

Links:
The Adventures of Stephen Fry
Mark Carwardine