It allows closed source project.
It allows propretary projects.
It allows derivitve works.
It allows the derivitive to be licensed by any license the author wishes (no copyleft provision).
The ONLY thing it requires is the copyright and notice to be included with any derived distribution.
Somehow RealSolid still managed to figure out how to fuck it up (as well as trying to copyright his stolen work).
RS just wanted to pass the MIT licensed Bitcoin code off as his own work. As a benefit from this, he could attack other chains that copied his ideas for being unauthorized derivative works of SolidCoin.