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: Green Dot (Nasdaq: GDOT) popped 12% in intraday trading today, after competitor Western Union (NYSE: WU) reported better-than-expected earnings and raised guidance.

So what: Western Union's EPS of $0.42 beat the $0.38 consensus estimate and rose 19% year over year. Its revenue of $1.37 billion beat the $1.33 billion consensus forecast and rose 7% year over year. Management raised 2011 EPS guidance to between $1.48 and $1.53, from previous guidance of $1.41 to $1.46.

Now what: In May, Green Dot missed earnings expectations but boosted its full-year outlook. Its volatile stock has fallen by more than half from its 52-week high this year in a series of plunges. Revenue growth of more than 35% in Western Union's electronic channels business, which accounts for 3% of revenue and competes with Green Dot, bodes well for Green Dot's outlook, as does Western Union's improving confidence in its outlook.

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