Ars Technica's Chris Foresman notes that test builds of Leopard's newest update, version 10.5.6, are arriving more frequently, perhaps signaling that the software is nearly ready for the public.
Build 9G38, the latest, notes that there are no known issues with the build, a crucial last step in the development process. Prior builds addressed issues with MobileMe, Time Machine reliability over AFP, Mail, and a long list of other "focus areas." The build was released last week.
Foresman closed by saying "though the signs point to a release soon ... I do not recommend holding your breath." Always good advice.