Well fortunately there are not too many bugs, but thanks to Dan Langille, we have a bugs database where bugs are reported. Generally, when a bug is fixed, a patch for the currently released version will be attached to the bug report.
The directory patches in the current CVS always contains a list of the patches that have been created for the previously released version of Bacula. In addition, the file patches-version-number in the patches directory contains a summary of each of the patches.
A "raw" list of the current task list and known issues can be found in kernstodo in the main Bacula source directory.