Personalized Internet radio company Slacker has raised $2 million in a $6 million round of funding, according to a new SEC filing. In late 2009, the company's previous SEC filing revealed it had raised about $12.1 million of a $14.2 million round. Various estimates put the company's total funding in the $70 million area.

Last year, Slacker decided to abandon its portable music device to concentrate on mobile apps. (Slacker's G2 device will be phased out over the second half of 2010.) That puts it more squarely in competition with Pandora, which offers a similar streaming service (both PC and mobile). The company currently offers ad-supported streaming apps for iPhones, Android and Blackberry devices (and, soon, Palm's webOS). An ad-free version of its PC and mobile service costs $4.99 per month ($3.99 per month if a one-year subscription is purchased).

At the 2010 CES, Slacker showed off a new caching feature that allows a user to sync cached stations over the air or via an Internet connection. When this new version is released to the public, it will be available only to premium subscribers.