Starting today, SoundHound Infinity for iPhone ($4.99) gets infinitely more useful. The latest version, SoundHound Infinity 3.6.1, includes a recommendations feature that suggests other songs you'll like based on the ditty you've just chosen to identify, either through recorded "tagging," text, humming, or singing the tune into the app.
SoundHound uses a proprietary engine based on intelligence collected from a combination of users' tagging behavior, a database of artists, and a list of underplayed songs--the latter composed of songs that are popular within SoundHound but receive less radio attention, if any at all.
Recommendations engines are all the rage, and for good reason, too. Discovering your next favorite songs based on beats you already like was the impetus behind Pandora and its ilk, after all, and also the guiding principle behind Apple's iTunes Genius feature, also a recommendations engine based on your music library.
In addition to suggesting other songs you can view or buy on iTunes, the premium and free (ad-supported) SoundHound app also sees improvements to its social networking hooks. Sharing songs with Twitter, Facebook, and e-mail contacts has gotten more intuitive, and more useful now that you're able to ping multiple status updaters with minimal tapping.
SoundHound users on Android will see these recommendation and sharing features soon.