At The Motley Fool, we poke plenty of fun at Wall Street analysts and their endless cycle of upgrades, downgrades, and "initiating coverage at neutral." So you might think we'd be the last people to give virtual ink to such "news." And we would be -- if that were all we were doing.

But in "This Just In," we don't simply tell you what the analysts said. We'll also show you whether they know what they're talking about. To help, we've enlisted Motley Fool CAPS, our tool for rating stocks and analysts alike. With CAPS, we'll be tracking the long-term performance of Wall Street's best and brightest -- and its worst and sorriest, too.

And speaking of the best...
What do you do when one of the best bankers in the business upgrades the shares of one of the worst bankers in the business? Personally, I listen up. Because if there's one thing SunTrust Robinson Humphrey Capital Markets has, it's ... well ... way too many names. But if there's another thing SunTrust has, it's a reputation in CAPS for smart stock picking in the credit card space.

But is SunTrust so smart that we should follow its lead, turn neutral on Capital One (NYSE:COF), and get ready to begin buying? You be the judge.

What's in SunTrust's wallet?
We're not sure, but its portfolio contains nearly everybody who's anybody in the electronic payments world. Whether it praises or pans these candidates, the analyst seems uncannily accurate in its predictions:

Company

SunTrust says:

CAPS Rating

SunTrust's Pick Beating S&P By:

MasterCard (NYSE:MA)

Outperform

***

94 points

Visa (NYSE:V)

Outperform

***

18 points

America Express (NYSE:AXP)

Underperform

***

17 points

VeriFone Holdings 

Outperform

***

7 points

Yes, I know that Capital One is no longer just a credit card hawker. The company bought some bad banks back in the day, and SunTrust has a bit too much bad experience with bankers for my liking:

Company

SunTrust says:

CAPS Rating

SunTrust's Pick Lagging S&P By:

Provident Bankshares

Outperform

*

35 points

BB&T (NYSE:BBT)

Outperform

***

14 points

Still, Capital One's core business is cards. And when you come right down to it, picking winning credit card companies is what SunTrust does best. With the help of prescient picks such as MasterCard, AmEx, and Visa, this banker has earned itself a slot in the very top ranks of investors tracked by CAPS. It's also got a record of picking more winners than losers, and an enviable margin of victory; on average, a SunTrust pick goes on to outperform the rest of the stock market by a good 10 percentage points. Nice.

Why Capital One? And why now?
That still leaves us wondering why this brilliant stock-picker likes Capital One today. No one in the mainstream media seems to know the details of SunTrust's upgrade of the stock to "neutral." (I checked.) And SunTrust hated the stock in January, rating it a sell at $18 a share. Just three weeks, one announcement of bad news about monthly charge-offs, and a 44% drop in the stock later, Capital One's valuation equation has changed drastically.

Today, Capital One sells for just 0.48 times its annual revenue, which is cheaper than almost anyone else you can name in the banking sphere. Why, even Citigroup (NYSE:C) and Bank of America (NYSE:BAC) -- two banks that my Foolish colleague Morgan Housel has pegged as great candidates for nationalization -- sell for P/S ratios of 0.82 and 0.64, respectively. Among credit card companies, Capital One looks just as cheap, relatively speaking.

Foolish takeaway
Admittedly, it's hard to say whether Capital One is a bargain at this price. The company's not currently profitable. Shorts are betting heavily against it. And that dividend -- 14.8% as of this writing -- will almost certaily get cut. Unprofitable shops like Capital One just can't afford the luxury of such a lush yield.

But when you get right down to it, SunTrust isn't yet saying you should buy Capital One. It's just positing that the bulk of the damage has already been done, and that shorting the stock is no longer worth the risk. I agree.

BB&T is a Motley Fool Income Investor selection. American Express is an Inside Value pick. The Fool owns shares of American Express.

Fool contributor Rich Smith does not own shares of any company named above.  disclosure policy.