File Comparing and Diff type plugins

File comparisons will show you what licenses have changed between version, or what buckets have changed between versions.

Once you choose (files to compare)[http://www.fossology.org/projects/fossology/wiki/Compare-picker] you jump into either the

1. (License difference tool)[http://www.fossology.org/projects/fossology/wiki/Compare-licensediff]
2. Bucket difference tool (works the same as the License difference tool)

These give you a side by side display comparing the two file trees.