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 pizza slinger Papa John's (Nasdaq: PZZA) were fast-rising in today's trading and closed with a monster 20% gain.

So what: It's earnings season, folks, and so it shouldn't be much of a surprise that the Papa's big leap was thanks to an investor-pleasing earnings report. Despite a hit from marketing charges, Papa John's first-quarter earnings per share increased 8% from last year. That was far better than the $0.55 that Wall Street analysts had expected. Revenue, meanwhile, was up 6% from the first quarter of 2011 thanks in large part to 3% same-store sales growth in domestic company-owned restaurants and 8.4% same-store growth internationally.

Now what: In the company's press release, Papa John's CEO and founder John Schnatter said, "The year is off to a terrific start." I think it's safe to say that investors agree. Of course, it also helped that, in addition to the strong first-quarter numbers, Papa John's also boosted its full-year outlook, taking its expected earnings per share to a range of $2.40 to $2.50. Wall Street had been estimating $2.36 for the year.

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