If anyone follows this and happens to like GNU Global/ggtags (I did), there's a Pygments plugin released earlier this year that enables it to use any language that can be parsed by Pygments: https://github.com/yoshizow/global-pygments-plugin
The Pygments plugin is really awesome; it should prove useful even for those who don't use Emacs. For example, gtags lets you use vim/Doxygen/bash/less/etc. to access the tags as well.