The packages are identical apart from the debian/control file indicating the architecture. This is because of the Liquidsoap binaries included in the package, which will be more recent versions that those in your distro of choice.
If you would like to try either of these packages on a test server, please post any bugs you find in this forum, or on http://dev.sourcefabric.org
Before installation, please remove the python-mutagen package if installed:
$ sudo apt-get remove python-mutagen
This is because the Airtime package has a more recent, bugfix copy of mutagen bundled in.