git-difftool appears to serve exactly this purpose but it is very inconvenient because it allows to comparing files one-by-one only.
Preferable solution would be similar to comparing two directories using kdiff3.
Dmitry Smirnov [ Editor ] from Australia
With git/1.7.11 it will be possible to use command
git difftool —dir-diff
With git/1.7.10 (which is in Debian “testing” at this time) the following fragment of ~/.gitconfig:
[alias] diffall = !sh /usr/share/doc/git/contrib/diffall/git-diffall [diff] tool = kdiff3
allows to use command:
to use kdiff3 to compare tags (or branches) like if they were a real directories.