If you follow new technologies for the digital distribution and access of music, you've undoubtedly come across the name Spotify. In recent months, the Sweden-based service — which offers a deep catalog of high quality streaming audio via a rock-solid and intuitive desktop client — has racked up the press mentions on both sides of the Atlantic. Spotify's Daniel Ek will be presenting at the Future of Music Policy Summit 2009 (Georgetown University, Washington, DC, Oct. 4-6). Reserve your spot now!

Currently available only in Europe, Spotify recently made headlines saying that the service now generates more revenue for Universal Music in its native Sweden than iTunes. Which is why some were perhaps surprised when it was announced yesterday (August 27) that the previously submitted Spotify app had been approved by Apple for use on its iPhone.

With music listeners becoming more accustomed to listening on mobile platforms (thanks in part to the popularity of apps from Pandora and Slacker), it seems like Spotify on the iPhone could be huge. Whereas Pandora and Slacker employ the "customizable radio" concept, Spotify lets you listen to pretty much anything you can think of, on-demand. The iPhone app will even let you load up on tunes and play them when you're NOT on a wireless network (these aren't permanent downloads, however — they only last as long as you keep your subscription current).

But there is a catch — the desktop version of Spotify (again, not yet available in America) lets you listen to songs for free, with an audio ad popping on every 15-or 20 minutes. The iPhone version will be free to download, but will require a subscription (around £10 a month or £120 a year in UK — you gotta do your own conversion, kids!).

Many industry observers (including us) were keeping en eye on whether Apple would approve Spotify for the iPhone, which some suggested might negatively impact Apple's download-driven iTunes service. At the end of the day, however, it seems that the "hardware" mentality at Apple may have won over — a "must-have" app like Spotify could spur more sales for the iPhone and related devices.

Keep in mind that Rhapsody — a streaming subscription/download hybrid service — has been available in America for some time. They, too, recently submitted an app to Apple; no word yet if it's been approved. (Rhapsody's Tim Quirk will also be at Policy Summit 2009.)

Though not yet available stateside (rumors suggest it'll be here in Q3 or Q4), some Americans are already using Spotify via beta invite (and IP proxies). Wired's Eliot van Buskirk has called Spotify "a magical version of iTunes in which you've already bought every song in the world," and we like it a bunch, too. Could Spotify in the mobile space finally turn on the requisite number of consumers for subscription-based streaming to become viable? Will tomorrow's artists be able to count on such services as a meaningful revenue stream?

Only time will tell. One thing's for sure, it'll be really interesting to hear what Ek has to say about where he sees digital music heading, and what he imagines Spotify's role to be in that future. And you can hear it from the horse's mouth.