It's not just tomorrow morning's quarterly earnings report that SodaStream (SODA) investors should keep an eye on.

A crowdfunding campaign for a new soda maker -- SPRiZZi -- is starting to gain traction on Kickstarter.

Just 148 backers have pledged more than $33,000 to bankroll the first wave of machines, but the new beverage platform makes no bones about taking on SodaStream.

"Comparing the Drink Machine by SPRiZZi to the SodaStream would be like comparing the rotary phone to the iPhone," reads the website.

Yes, SodaStream just got called a rotary phone. It goes on to bash SodaStream several times.

SPRiZZi bills itself as the first in-home beverage dispenser that mixes, carbonates, and chills drinks. It's probably a closer kissing cousin to Green Mountain Coffee Roasters (GMCR.DL) in that it has a water reservoir, alters the temperature of the water, and pours out single servings of a flavored product.

Yes, it looks and sounds neat. A big problem will be price. Kickstarter backers can get a machine for as little as $197, but the machine plans to retail for $399. SodaStream systems can be had for less than $100.

Another problem is investing in an unproven platform. When someone buys a SodaStream maker -- or a Green Mountain Keurig machine -- they know that flavor refills will be plentiful. Can the same be said about SPRiZZi, especially if sales don't take off?

SodaStream bears pointed to Primo Water's (PRMW) FlavorStation as a potential SodaStream slayer two years ago. The bottled water distributor had plenty of retail connections for its flagship H2O but it only managed to get one major retailer -- a home-improvement superstore chain, at that -- to sell FlavorStation carbonators and flavors.

Early adopters may try anything, but mainstream beverage drinkers will wait until a platform is proven, cheaper, and readily available.

It's still a development worth watching as the first SPRiZZi systems are expected to ship in August. After the success of the Pebble smart watch on Kickstarter, one can't disregard all potential start-up threats. However, it will take more than an army of 148 iPhone sippers to wash away the globally popular rotary phone of carbonated beverages.