zcov is wrapper around the basic facilities of gcov for generating pretty summaries for entire code bases. It is similar to lcov with an emphasis on nicer HTML output (including, for example, branch coverage), and a greatly simplified command line interface which tries to work around deficiencies in the metadata provided by gcov.
A beta version is available here: zcov-0.02.tgz. Please send bug reports and feedback!
The zcov source is kept in a github repo at: http://github.com/ddunbar/zcov
Sample output for Clang.
Email daniel (at) zuster.org for more information.