Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of fuel cell technologist Ballard Power Systems (NASDAQ:BLDP) soared 13% today after its quarterly results and outlook topped Wall Street expectations.

So what: The stock has skyrocketed during the past year on optimism over growing fuel-cell adoption, and today's Q4 results -- adjusted EBITDA swung to $0.2 million vs. a year-ago loss of $3.2 million as revenue climbed 5% -- coupled with upbeat guidance only reinforce that momentum. In fact, gross margin expanded 600 basis points sequentially to a solid 34%, suggesting that its cost structure and competitive position is improving in the process. 

Now what: Management now sees full-year revenue growth of about 30% on breakeven adjusted EBITDA. "The Company expects the positive growth trends in 2012 and 2013 to continue in 2014 with a similar trajectory, as Ballard continues to pursue its growth strategy for fuel cell product sales, engineering services and IP licensing," said Ballard in a statement. Of course, when you couple Ballard's still-speculative business model with the stock's red-hot stock price -- now up a whopping about 400% from its 52-week lows -- average investors would do well to stay on the sidelines. 

Brian Pacampara has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.