. . . noted Alternate History author S. M. Stirling?
Yes, it's true, at least according to a press release published last Thursday (March 24) by Conan.com. The rest of the press release is short on details, but does reveal that the novel - Conan: Blood of the Serpent - will serve as a prequel to the classic Conan adventure Red Nails - a personal favorite of mine due to its opening featuring Conan battling a stegosaurus.
A big thank you to the DMR Books blog and their weekly DMRtian Chronicles posts for bringing this piece of news to my attention.