If you are using music notation software, you should visit Linux Journal website and read an article Music Notation Programs: Recent Releases. Dave Phillips have recently presented the most interesting additions and new features of Linux notation applications.
Dr. Joerg Anders released a new version of his NtED notation editor. MuseScore 0.9.1 is also available.
Meanwhile, LilyPond itself continues to mature. LilyPond stable is now at version 2.10.33.
And lastbut not least, Gcomposer. Cedric Roux, a.k.a. sed, describes his application as “a little tool to write music”. Gcomposer is best for the guitarists.