renames show up as add+remove in Web UI
For example, look at this commit:
and compare to the way it's displayed here:
http://github.com/git/git/commit/a3df180138b85a603656582bde6df757095618cf (click the "Show Diff Stats" button to see the rename info)
The Bitbucket version shows all the lines of the three renamed files being removed and then added under the new name whereas the kernel.org and GitHub versions only show the diffs for the one file that actually changed.