Apparently he's changed his mind, as Noyce told Moviehole that any further adventures of Evelyn Salt will be taking place without him...
Noyce: Those 3 [alternate] Blu-ray cuts [of the film] represent just about everything I have to offer on Everlyn Salt… If there ever is a sequel, better its directed by someone with a completely fresh take on what I believe could be a totally entertaining and complex series of stories.
Even though Salt was met with a mostly lukewarm response, I can see further installments improving on the setup established, and like I said before Jolie makes for the type of action star I want to see more of.
Salt actually comes out on DVD today, so if you're interested you can pick up a copy right here