Ever since I have installed the GarageBand 2.0.2 update, Shrook has become extremely unstable. When I launch it, and leave it in the background, I get a Bad access exception in CFNetwork while doing a http read. I don't know what was included in the GarageBand that would cause this problem.
But since Shrook is not working, I downloaded and registered NewsFire. I haven't used it since the author made it shareware, because I had paid for Shrook. But, after registering it is a great RSS client.