Since going public earlier this year, Visa (NYSE:V) hasn't disappointed investors. Shares have gained nearly 40%, providing perhaps the only ray of hope in a world where "financial" has become an unspoken curse word.

Third-quarter earnings didn't disappoint, either. Net income came in at $422 million, or $0.51 per share, on revenue of $1.6 billion. In the same quarter last year, Visa logged $299 million in net income. Since it wasn't a public company back then, per-share comparisons are irrelevant. Payment volume over the previous year surged 19%, the number of cards with the Visa moniker grew 14% to 1.6 billion, and total transactions grew 15%, to 10.7 billion. All in all, it was a pretty spectacular quarter for Visa.

As has been the case with rivals Mastercard (NYSE:MA) and American Express (NYSE:AXP), a good slug of Visa's growth came from outside the United States. For the quarter, payment volume grew 12% in the U.S., 26.5% in the Asia/Pacific region, 40.4% in Central Europe/Middle East/Africa region, and 47.5% in the Latin America/Caribbean region.

All good news here. Visa is doing fantastic, no doubt about it. Here's what's likely crossing investors' minds right now: How much longer can cash-strapped consumers keep charging up their credit cards, and is Visa a good investment today?

To address the first point, I don't think it's a coincidence that in the same quarter Visa reported a surge in transactions, Bank of America (NYSE:BAC), Citigroup (NYSE:C) and Capital One Financial (NYSE:COF) reported problems with customers' ability to actually pay their credit card bills. Of course, this point doesn't include the 61% of Visa's quarterly transactions from debit cards last quarter, but it still holds some weight if the battered consumer taps out his last source of financial ammunition: credit cards.

Second, is Visa cheap? It's growing fast, and is likely to do so for some time to come. Management raised its outlook for 2008, guiding toward operating margins in the mid-40% range, and through 2010 expects revenue growth between 11% and 15%, EPS growth of at least 20%, and free cash flow in excess of $1 billion. All pretty impressive stuff.

But with a market cap of around $85 billion, nobody's cutting you a deal for that success. On average, analysts expect Visa to earn $2.03 in 2008, and $2.55 per share in 2009. Let's say they're dead wrong and it ends up earnings $3.00 per share next year. That would still put Visa at over 25x next year's earnings -- not exorbitantly expensive, but there's little room for error, as well.

Bottom line
If you're a true believer of Visa as a global growth story, the stock will likely keep you happy over the next several years. If you're a little hesitant about the effects of a slowing global economy and don't want to jump into a stock selling a premium, this one probably isn't for you. I'm sticking with the latter, although our CAPS community currently gives Visa a 4-star rating. If you'd like to throw in your input, click here to come on over to CAPS and tell us what you think.

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Bank of America is a Motley Fool Income Investor selection. American Express is a Motley Fool Inside Value pick. The Fool owns shares of American Express. Try any of our Foolish newsletters today, free for 30 days.

Fool contributor Morgan Housel doesn't own shares in any of the companies mentioned in this article. The Fool has a disclosure policy.