After Spotify CEO Daniel Ek's previous comments, reported on Pocket-lint, that "I'd love to work with someone like Last.fm" and promising an announcement within days, many expected the two companies to team up.
However, as we also reported, Spotify looked to be tapping up another company for its recommendations engine - Echo Nest. The company is built around two MIT PhDs and does pretty much the same thing as Last.fm - recommending tracks based on your previous listening.
An early implementation that builds playlists around selected tracks was demonstrated to attendees at SanFran MusicTech on Monday. The results have been described by eyewitnesses as "like (Apple's) Genius, only much better".
The company is promising other implementations in the future too. Currently Spotify's "radio" functionality is very weak compared to its competitors, so this partnership will bulk up one area in which the streaming service is seen as lacking.
No release date has been announced for the implementation of Echo Nest's recommendations to users. We asked Spotify whether it would be offering the functionality free or using it to bulk up its premium offering. They told us: "Nothing has been decided yet but we'll let everyone know once we have something to share".