Music streaming companies are pulling out all the stops lately, whether to pre-empt tomorrow’s launch of the much-hyped Beats Music service or to stay ahead of the intense competition. This includes Spotify, which announced today a partnership with Topspin that allows artists to list their merchandise on Spotify for free. Artists can now list their T-shirts, posters, and other merchandise on their Spotify page. When fans click the “Buy” button, they will be sent to the artist’s online store to buy the merchandise. Neither Spotify nor Topspin will charge artists any fees for this feature. Spotify has been looking to improve its relations with artists, and this move may help. Music streaming services in general, and Spotify specifically, have come