UPDATE: This story was updated on February, 4, 2009.

Infusionsoft, the provider of marketing automation software for truly small businesses is truly devoted to its intended customer base. So much so that it guarantees to double the sales of any small business that signs up for its Web-based software. The young CRM player has been making a lot of noise lately. Earlier this month, Infusionsoft announced its tiered approach to pricing and delivery of its solution.

In late December the company also announced a new round of investment — $7.9 million in Series B financing. Dave Lee, Infusionsoft’s vice president of product and marketing told me that despite economic conditions, things haven’t appeared to slow down for the company. Interest among small businesses continues to skyrocket, he said. “Especially in the small-business world that we live in — 25 employees or less — you’d think they’d be hurting,” he told CRM in an interview in early January. “They’re the ones that are being really smart and are thriving right now…. It’s very encouraging to see there’s demand out there.”

What’s also encouraging is Infusionsoft’s faith that its customers will succeed after turning to its product. The “Double Your Sales” idea sprouted from an experimental contest last year, in which the company challenged a company (All About Spelling) to double its sales for free software. All About Spelling succeeded by a landslide, proving to the Infusionsoft team that doubling an organization’s sales is an obtainable feat. It will be interesting to see what kind of return this “Double Your Sales Guarantee” brings for the company. It’s a pretty powerful concept — especially considering the less-than-friendly economy.