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 infrastructure services company Quanta Services (NYSE: PWR) were getting a big boost from investors today, rising as much as 13% in intraday trading after the company announced third-quarter earnings and a big new contract.

So what: Third-quarter results for Quanta were fine. Revenue of $1.25 billion was up from $1.21 billion last year and ahead of the $1.21 billion that Wall Street was expecting. Earnings per share fell to $0.25 from $0.30 in 2010, but matched analysts' estimates.

While investors may be plenty satisfied with those results, what's likely driving most of the stock's gain today is the announcement that Quanta will be part of TransCanada's (NYSE: TRP) Keystone XL Pipeline project through the MPS Constructors joint venture. The project will build 1,179 miles of pipeline and related infrastructure from Hardisty, Alberta, to Steele City, Nebraska.

Now what: While the details of Quanta's role in the project are still yet to be hammered out, the company expects that it will play a "significant role." CEO Jim O'Neil called Keystone XL Pipeline "the largest individual infrastructure project on the horizon in the industries we serve" and said that it would likely create at least 2,000 construction jobs at Quanta alone. That seems like good reason for investors to be excited about the company's future.

Of course, if there's a hitch that Quanta shareholders need to keep in mind as they celebrate today, it's that Keystone XL still hasn't been approved and has been hotly debated. There will obviously be little to celebrate if it ends up that Quanta is part of a project that never happens.

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