Please add support for Libre.fm, witch is a free implementation off Last.fm.
http://libre.fm/

It's planned, I want to make it possible to submit to both at the same time.
In the meantime, you can just replace "post.audioscrobbler.com" by "turtle.libre.fm" in the file plugins/audioscrobbler.pm


i know this is quite an old topic, but i started modifying the audioscrobbler-plugin to support libre.fm.
currently you can choose to scrobble to either last.fm or libre.fm, not both at the same time.

after a short discussion on #gmusicbrowser i think that the libre.fm scrobbling might end up as a separate plugin at some point due to changes in the last.fm web-api. (that would obviously bring the feature of simultaneous scrobbling.)

if you want to try my modified audioscrobbler-plugin, feel free to check it out here (use the "raw" link to get the file).
feedback highly appreciated.

disclaimer: this is a working but not yet final version of the plugin! it might be modified in the near future, i'll try to note the changes here, otherwise you can watch my github-repo.