Pandora Media’s mobile offering isn’t having a lusty affair — it’s just no longer going steady with the iPhone. The free personalized radio company is available for Windows Mobile handsets too, as of today.

Last July, Eydie filled us in on Pandora’s iPhone offering — the company’s first free offering in the mobile space. (At that point, AT&T and Sprint customers were already able to access the service for a fee.)

The Windows Mobile version, like its iPhone cousin, lets users key in any artist or song to create a custom Internet radio station. Right now it works with the Sprint HTC Touch, the Verizon XV6900, and the Motorola Q9c on Sprint and Verizon.

Pandora is off and running with mobile advertising experiments on its iPhone app, and is sure to do the same with its other handsets. Earlier this month, Target expanded its banner ad campaign with Pandora to promote its exclusive sale of Christina Aguilera’s new CD release. Big-name retailers and advertisers Best Buy, Microsoft, Proctor & Gample, Nike and others have already tested out ads on Pandora’s iPhone app.

Precious mobile eyeballs flock to Pandora. In less than five months, Pandora has reached 2 million downloads from the iPhone App Store (which equals it reaches about one in every five iPhone users) making it one of the most downloaded free applications on the handset.

Pandora’s targeting capabilities offer a way for brands to finely tune their ad messages to a defined audience. You can target by age, gender and ZIP code. According to Mobile Marketer, Pandora claims that its iPhone ad platform has delivered more than twice the response rates compared to its other ad products due to the highly interactive nature of the device.