Last.fm realized strong user growth in several key categories after launching it’s free-on-demand streaming service recently. In the United States, Last.fm’s unique listeners increased 85% on the day of launch (Jan. 23) versus the previous Wednesday (Jan. 16). Listening metrics are considered especially relevant as a method to measure a user’s engagement with the site. In addition, the site realized a 45% increase in page views and 27% increase in unique visitors in the U.S. during the same time period.

The site’s momentum continued yesterday as unique listeners increased 80% as compared to the previous Thursday. Page views and unique visitors also increased 60% and 31% respectively during the same time period.

In launching the free-on-demand service earlier this week, Last.fm became the first music web site to offer free, global, on-demand access to the largest licensed catalogue of music built on partnerships with all four major record labels – including Universal Music Group, Sony/BMG, Warner and EMI – as well as CD Baby, IODA, the Orchard, Naxos and more than 150,000 independent labels and artists. Free-on-demand listening is available without registration, or the download of any software.

(Editor’s note: What we should observe is how Last.fm can sustain this and not just a one time growth as expected on new services being launched.)

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