Vonage (NYSE: VG) has never been a stock for timid investors. In the last five years, share prices plunged from more than $5 to mere pennies, then back up over the $5 mark in early 2011 only to get a 50% haircut again.

This week, the grand tradition of hackles-raising thrills and spills continued. Vonage shares are down more than 20% in the last five days thanks to an underwhelming fourth-quarter report.

The large move is not surprising, though its direction wasn't a sure thing. Whenever you expect Vonage to zig, the company zags. Tell the stock to jump, and it doesn't ask, "How high?" It is just as likely to play dead instead.

I find it funny that the stock is getting punished because management is doing exactly what I was hoping they might do -- increase marketing efforts to stimulate top-line growth. A stronger marketing push is the right way forward when you consider that Vonage customers rarely leave once they've signed up. Vonage's 2.7% monthly churn compares very favorably to other consumer-oriented subscription services.

Management expects EBITDA and earnings to suffer in 2012 as the company steps up its marketing efforts. "The time is right to increase our investment in organizational capacity and marketing," said CEO Marc Lefar. And it doesn't hurt that the mobile calling app Vonage introduced last week has taken off like a bottle rocket with nary a marketing dollar spent to support it.

Unlike more enterprise-focused VoIP rivals 8x8 (Nasdaq: EGHT) and Cbeyond, Vonage caters almost exclusively to consumers. That Everyman focus absolutely requires an effective marketing program, while 8x8 could get by with just sending sales reps on a tour of major business parks.

Granted, increased ad spending doesn't necessarily lead to higher sales -- the campaign must also strike a chord with the target audience. But higher budgets are a good start.

So do I still like Vonage now that the company is doing what I was hoping for and the stock is available at a fresh discount? You betcha. My bullish CAPScall stays firmly in place, and I might even go scrounging for loose change under my couch pillows to take a more hands-on advantage of this situation. If that marketing effort gains traction, Vonage should do very well over the next several years.

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