The era of paid music downloads is coming to an end (despite the fact that online sales are growing).

Qtrax, which has signed all four major labels (EMI, SonyBMG, Universal Music Group and Warner Music Group), launched yesterday with 25 million songs (compared to around 3 m for Amazon and 6 m for iTunes)

It isn’t pretty - the downloaded songs are not compatible with iPods and have to be played via a proprietary player built on the Songbird platform. Ads are displayed during playback, even on music devices. For now the service is Windows only, so Mac users are left out. And right now the service is down completely from all the attention it’s getting.

For most people, BitTorrent and the music search engines are all they need for their illegal-but-highly-convenient music needs. Any additional hurdles means not a ton of usage. And since services like Imeem and Last.fm provide free on demand streaming music with ads, there is already real competition out there for Qtrax.

But the trend is clear - labels have given up on DRM completely and are willing to experiment with ad supported free downloads. Once they give up on the ad supported part of the model and just realize that recorded music is nothing more than marketing collateral for other revenue streams like live performances, we’ll have gotten somewhere. But my guess is that one of the labels has to go out of business first for that to happen.

Soon as I get a chance, and can download their software, I will give you an update on how it works and if you can copy the music to your Sansa.