Buraks has released Action Script Viewer 3. The latest version can decompile Macromedia Flash 4, 5 and MX SWF files.
I know some of the people in the community would want all information about tools such as this to be secret. Personally I think its important to know how easy it is for people to steal your code, and how unsafe information in an SWF file really is.
[Via Flazoom]