Not sure why this wasn't given more of an announcement, but the first cumulative hot fix for ColdFusion 9 was released yesterday. Hit the link up for details on what was fixed. The best item I think is the JSON casting issue. I talked about that bug in a blog entry back in October.
Edited: A tip for Mac users. I noticed when I double clicked on the zip that my Mac extracted the jar and automatically extracted the contents. Since the CF Admin wants the jar, I wasn't sure what to do. On a whim I went to the command line and found that I could use "unzip". I simply unzipped the file there and it just extracted the jar.