This new Camelot series is supposed to be on Starz in 2011. I haven't really heard much more about it. But Michael Hurst is also doing some sort of Agincort series too, so there's more medievalesque material coming to the premium channels.
I just hope Season 3 of Merlin goes in the right direction. After all Hex died quickly, and they ruined their own Robin Hood, so hopefully Merlin can survive its projected five seasons.