According to the latest leaks, Mac OS X 10.5.6 is almost finalized. The last build, the 9G38 distributed to the developers is not supposed to contain any bugs, the tests primarily are focused around MobileMe.
This update will be important because it will standardize the system over the whole range, since at present the new portables have a specific version of Mac OS X 10.5.5.
[translation by crispin]
