UK digital music service, 7 Digital, today launched its digital music service in the US, while also making a grab at the mobile market with launch of a music download store for BlackBerry users.

7 Digital is well-known in Europe, but is raising the bar in competition in the US with its launch there. Tracks will cost 77-cents, or $7.77 for an album (standard prices, variable prices also exist).

Tracks are sold in high-quality 320kbps MP3 format, completely free of DRM. The company also offers a “digital locker” in which all your downloads are backed-up on 7 Digital’s servers in the even you need to redownload them in case of computer failure.

For BlackBerry, 7 Digital is offering a free application through the BlackBerry App World store, also making the app available through its own website. The app offers BlackBerry users access to the company’s full catalogue of 6 million songs from the majors and indie labels. All sold in unprotected MP3 format.

It’s an intelligent app – if a user purchases a song while using a poor wireless connection the app will download a lower quality version, replacing this with a high-quality variant when the user enters range of a previously used WiFi network.

The moves mean 7Digital is now putting up a fight for marketshare in the US against Apple and Amazon, selling tracks at higher-quality than the market leader, Apple.

The company is announcing the new initiatives at a London event this morning, which this commentator is trying to get to right this moment.