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MeeMix today went live with a public testing version of its Internet radio website. MeeMix faces plenty of competitors, such as Last.FM, Pandora and Slacker.
Meanwhile, another competitor, New York's Spiralfrog, has just raised $2 million in debt. And yet another, Jango, is worth a mention. More on those in a sec.
First, MeeMix. This company hopes to change things by streaming music it thinks matches your taste. You're only required to enter one song or an artist’s music that you enjoy. MeeMix analyzes a song's parameters, such as its genre, and sub-genre, along with information about you. It's algorithm then generates a customized station for you. In this way, it is more like Pandora than Last.Fm. Last.Fm focuses less on the components of music when it makes recommendations.
Located in Tel Aviv, MeeMix focuses solely on the U.S. market. The company cannot provide services in Israel because of licensing issues. However, MeeMix asserts that it is working on resolving those issues.
Meemix's music catalog is limited. Although the company claims that it recently doubled the number of artists in the catalog, its size is still limited compared to larger players such as Last.FM or Pandora. It makes money from advertising.

SpiralFrog, meanwhile, is facing trouble reaching actual profitability. Last quarter the company lost $3.3 million, and earned only $20 thousand in actual revenue. It's understandable that venture capitalists are hesitant to provide further funding for the company, and thus the debt. It also hopes to make money from advertising.
SpiralFrog’s service has also been deemed as unreliable, at times giving users more error messages than actual music.

Jango
Jango also offers an embeddable widget, dubbed Jango Jukebox, that is completely customizable by the user. The widget features scrolling images of artists that allows viewers to select an artist image and play that artist's music.