Shares of at-home beverage maker SodaStream (Nasdaq: SODA) have taken a beating in the last couple of weeks.

After its stock price rose to $48.13 in anticipation of strong earnings, the slow unit growth of its soda-makers left shareholders feeling flat. Shares dropped nearly 15% following the earnings release, and the slide continued last week, when rival Primo Water (Nasdaq: PRMW) announced it was teaming up with Sparkling Drink Systems to produce a new line of carbonated-beverage makers featuring Freedom Sparkling System technology.

Primo, primarily a spring-water-system purveyor, had earlier rolled out FlavorStation, its competitor to SodaStream, but flavoring problems hampered the debut of their soda system. Now Primo appears to have upped the ante: Its venture with SDS will offer 70 different beverage appliances to suit a range of needs, priced from $40 to $300. Serge Bueno, CEO of Sparkling, said the two companies hope to offer soda at prices equivalent to less than $0.20 per can.

News of the strategic alliance sent Primo shares up more than 10% at their high last Tuesday, while SodaStream continued to fall, to under $35.

Cola Wars II
Not to be outdone, SodaStream unveiled its own updated beverage maker on Monday. Dubbed the "Revolution," the enhanced machine allows the user to control the level of carbonation, reduces the amount of time needed to make a liter of soda to just 30 seconds, and shows the level of CO2 remaining in the cartridge. Investors seemed to like what they saw from the Revolution, which will hit stores in the third quarter, sending shares up over 10%.

The Revolution is just one of several additions that the upstart soda-maker has promised for 2012. New flavors using the plant-based sweetener Stevia, as well a partnership with Kraft (NYSE: KFT) to produce Crystal Light and Country Time Lemonade brands for SodaStream, provide other growth opportunities.

Since its founding in 1991, SodaStream has sold more than 10 million soda makers, 1.3 million of which were purchased in the United States, where its prime growth opportunity now lies. By comparison, Green Mountain Coffee Roasters (Nasdaq: GMCR), despite being valued at about 10 times as much as SodaStream, estimates it has only about 10 million of its Keurig single-cup coffee brewers installed in households.

We'll expect to hear more about Primo's new partnership, and the prospects for FlavorStation when it reports earnings later this week. The company had previously lowered guidance on its FlavorStation products due to delays in reformulating flavors, so guidance -- rather than Q4 numbers -- will be the big news. SodaStream, meanwhile, has expanded around the world and plans to enter South American and India later this year. 

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