mhensley said:I've see mentioned that they will release one new setting per year. Considering that 4e will probably be around for 8 years, prehaps the release schedule will look something like this:
2008- Forgotten Realms
2009- Eberron
2010- Greyhawk
2011- Planescape
2012- Dragonlance
2013- Dark Sun
2014- Mystara
2015- Ravenloft
Except that 5E will be published on or before 2013, which throws a wrench in your calculations.