Curtis Melvin notes that Google Earth has updated some of its Pyongyang imagery. Looking around the Central Party complex, it seems Kim Jong Il is having one of the two residences near his main office (Residence #16) renovated or torn down. Here is an image from March 2009:
And here is an image from December 2009. Note that part of the structure tagged Residence #16 has been demolished:
I will leave the speculation to others, but perhaps KJI is making room at the Central Party complex for his successor. In the mean time, here is a little overview of the Central Party neighborhood.