By Richard Saintvilus

On Friday, shares of Internet radio giant Pandora (P) plummeted by almost 17% -- closing at $10.47 per share when rumors surfaced that Apple (AAPL) was looking into entering the already crowded space of streaming audio entertainment, an environment that includes (among others) Spotify and Sirius XM (SIRI). Although just a rumor at this point, I couldn't contain my immediate reaction: "It's about time."

You see, when it comes to music Apple is far from an amateur. After all, its popular iTunes platform not only revolutionized how songs are bought and sold, it saved the music industry altogether -- from the likes of Napster, Bearshare as well as any other rogue outlet or application seeking to steal the works of artists under the pretext of "freedom." Now, if it indeed wants to take it a step further, the music industry must oblige. It's their duty.

Pandora and possibly SiriusXM just might become innocent casualties of Apple's bigger targets, Samsung and Google (GOOG), both of which are in a neck-to-neck race with Apple in the nasty fight for smartphone supremacy.

Samsung recently launched an attack on iTunes with what it calls Music Hub, a mobile music service designed for its latest line of Galaxy smartphones. A new Apple streaming service could be seen as retaliation.

What I found interesting is although Samsung's announcement arrived two months ago, it has had no material impact on neither Pandora nor Sirius XM's stock. Well, Samsung is not Apple.

The Apple rumor on the other hand was a punishing hit to Pandora's stock, stemming from a combination of things, including the anticipated ease of integration. It stands to reason that consumers might be able to turn Apple's top-selling mobile devices (iPhones, iPads and iPods), many of which likely contain existing songs purchased from iTunes into a supreme streaming platform -- one capable of being enhanced by the intelligence of Apple's iCloud.

Although shares of SiriusXM held pretty steady, I think this just might be a blow to those who insist that the Sirius' satellite delivery platform is sustainable and unthreatened by IP. Think again. With the possibility of Apple in the mix, Pandora and Sirius may find it difficult to acquire and maintain subscribers -- particularly if the rumor is true that Apple's service would be advertiser-supported​. This means it would likely be free to the consumer.

While Sirius has done exceptionally well with recent rivals and growing its subscribers respectably, can it compete with a free Apple? Not many have proven to be able to compete on price -- much less free -- despite Apple products being priced typically higher than the alternatives.

What's more, based on the features offered by Samsung's Music Hub, including allowing users to upload and store their own music for on-demand access, the advantages once enjoyed by Pandora and Sirius will now be overtaken.

First it was Samsung, now possibly Apple. Sadly for Pandora and Sirius, any level of success generated by these two big players will likely attract others -- names such as Google, Amazon (AMZN), and perhaps even Microsoft (MSFT) might soon enter the mix.

Remarkably, we haven't even touched upon Research in Motion's (RIMM) Blackberry Music service, which currently has an impressive number of subscribers. However it is hard to imagine that Apple will enter any environment without intent to dominate.

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