There haven't been any official conversations. But after the big "Rise of the Planet of the Apes" opening last weekend, the movie's writer/producers not only expect a sequel or two -- they are prepared for them.
Wow! Can't wait for it! I enjoyed the movie very much even if I were alone. My sibling were all into Captain America so I have to watch the Apes alone :) Watching it alone was weird. But had a blast watching it!
But the producers are not 100% sure if they will have a sequel they are still on the "wait and see" mode :)
But if ever they are working on a sequel that's good and if there won't be a sequel that's OK since I am satisfied with the movie. Sequels tend to be a disappointment and the first one would always give you the strongest impression and the sequels would have a harder time to beat that.
The only movie series that I like are: Toy Story (love them from 1-3)
Movies with sequels that I don't like: Cars (I am sorry but I was not satisfied with Cars 2), Hang Over (hang over 2 -- don't like it. seems like the same old joke been repeated again and again).