Beats, beans, and books colored in the week that was.

Staring at the satellites
With nearly 5 million subscribers, satellite radio isn't exactly a well-kept secret. XM Satellite Radio (NASDAQ:XMSR) and Sirius (NASDAQ:SIRI) certainly haven't been neglected by the market. Each company commands a market cap of roughly $6 billion. However, some folks still seem to be taken by surprise at how quickly these companies are growing.

This past week, both companies put up their quarterly numbers, and the potential is coming in loud and clear. XM was up first, with revenues more than doubling to $119.9 million and a markedly narrower loss. Sirius saw its deficit widen yet still had revenues more than quadruple to $43.2 million.

Some investors may be waiting for the companies to prove that they can become profitable -- and sustain that profitability -- but it's unlikely that either company will be valued at $6 billion, or less, if or when that day arrives. In a Motley Fool radio interview, XM CEO Hugh Panero projected that his company "could have well over 20 million subscribers by 2010." Sirius is still well behind XM on the subscriber and revenues front, but it's growing up in a hurry.

You've got your Tazo mixed up with my Chantico
Is Starbucks (NASDAQ:SBUX) everywhere? That certainly seems to be the perception out there. Remember when Bart Simpson was walking through a mall where every other store was a Starbucks? Did you hear comedian Lewis Black's bit about coming to the end of the universe in Texas when he walked out of a Starbucks, only to find another Starbucks across the street? Guess what? Those shots at Starbucks were taken years ago, and the company is still growing aggressively. The company tacked on 669 stores over the past year and claims that there is room for 30,000 locations worldwide -- more than three times as many as are open today.

So maybe the notion that the premium coffee market is fully saturated is just wrong. On Wednesday, the company saw its March quarter revenues climb by 22%, with its earnings improving by 26%. With the company's growth brewing overseas, now that the stock is down substantially since it peaked at $64 back in December, perhaps the stock has become what its coffees have never been -- cheap.

Book it, just book it slower
To put Starbucks' growth in perspective, remember that speed demon Amazon.com (NASDAQ:AMZN)? Well, this past week, the company saw its March quarter sales climb by just 24%. This doesn't mean that Amazon's heady growth days are over, but it does mean that maybe the stock can be better appreciated as the cash cow that it has now become.

Other online retailers like Rule Breakers recommendation Overstock.com (NASDAQ:OSTK) may be growing substantially faster -- Overstock saw its top line more than double this past quarter -- but Amazon is still worth watching as a way to capitalize on the world's continuing migration online.

The headlines behind this week's stories:

Until next week, I remain,

Rick Munarriz

Longtime Fool contributor Rick Munarriz is a Sirius satellite radio subscriber as well as frequent customer of Amazon and infrequent patron of Starbucks. He does not own shares in any of the companies in this story. The Foo l has a disclosure policy. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early.