I really, really liked The Lion, The Witch, The Wardrobe. Prince Caspian less so. Voyage of the Dawn Treader even less so. The series definitely got worse as it went along.
Looking at wiki, it seems without Walden Media the earliest we'll see the next film (Silver Chair) is 2018! Well there certainly is going to have to be some recasts ... the actor who played Eustence (a supposed eleven year old in SC) will be 25!
In 2018 it'll be 13 years since Lion and 8 years since Treader - I feel a reboot approaching.