Even if the news is still some days old - its worth mentioning: batman-advanced is now available in Debian!
The packages are available through your favorite dpkg frontend (apt-get, aptitude, ...) using the unstable repositories. To follow the package development you can visit the following pages:
batman-adv-source contains the source code and can be compiled for your kernel using module-assistant . batman-adv-battool contains the battool which provides ping, traceroute and other tools for the batman-adv network.
Big thanks to Sven Eckelmann, Simon Wunderlich and Holger Levsen for their work on these packages. :)
BTW, you also can find the current batman stable (0.3) in the lenny and unstable repositories. Here the respective package pages: