Bank bailouts in Europe -- and maybe even the countries themselves -- are bad, but thoughts of the Fed bailing out the U.S. economy with even more stimulus is apparently good news, because the Dow Jones Industrial Average jumped 162 points yesterday as comments from Chicago Fed president Charlie Evans indicated he would support action.

While I say a pox on both their houses, some stocks did much worse than the Dow, going in the other direction and falling by double-digit percentages. So first let's see whether they had good reason to drop, as panic-fueled declines can sometimes make for excellent buying opportunities.

Information, please
Financial data services provider FactSet Research (NYSE: FDS) plummeted 12% yesterday after reporting guidance that came in soft, despite a 10% increase in third-quarter revenue that generated an 11% increase in profits. As always, the market is a forward-looking machine, but in this case it seems as if the panic selling that gripped FactSet's stock may have been overdone.

The data provider expects the fourth quarter to show revenue of $208 million and profits of $1.17 per share at the high end compared to the $210 million and $1.21, respectively, that Wall Street anticipated.

The old adage to "sell in May and go away" seems to have been partly at play in FactSet's performance. World stock markets had their worst month in May since September 2011 as the European financial crisis reared its head again in a not-so-pleasant way, causing the euro to hit a near two-year low. FactSet is particularly sensitive to declining equity markets, as the volatility tends to make its customers more cautious, leading to lower demand for services from investment managers. The strong first quarter equity markets enjoyed gave way to worsening second-quarter fundamentals.

FactSet has enjoyed its position relative to Bloomberg and Thomson Reuters by being the low-cost data services provider, and while low price can go only so far and even be upset by global turmoil, it does speak to its ability to gain greater share still going forward. The stock-price decline yesterday was the biggest drop it's experienced in a decade, which suggests to me it was willy-nilly selling and will allow FactSet to bounce back.

I've rated the company on CAPS to outperform the market over the next several months at least, though I think it's quite possible it will regain its previous heights over the long run. It's likely the broader CAPS community agrees with that assessment, as 95% of the nearly 400 members weighing in on FactSet see it beating the Street.

Tell me on the FactSet Research CAPS page or in the comments section below whether you agree the sell-off was overdone, then add its stock to the Fool's free stock-tracking service to get the needed data on when it's ready to rise again.

Your move
That little nugget of information the investment banks withheld from the public ahead of Facebook's (NYSE: FB) IPO -- that their analysts were cutting revenue growth estimates -- seems to be showing up in the operations of social network gaming company Zynga (Nasdaq: ZNGA).

According to data compiled by AppData.com, which tracks Facebook apps, Zynga's daily active users dropped 8.2% in May, which led analysts to suggest that social network gaming, particularly on Facebook, had hit a "negative inflection point." The novelty is apparently wearing off, though that doesn't mean I'll be unblocking all those annoying game updates I get from friends on Facebook.

But if Zynga's user base is contracting, that's going to be more bad news for Facebook since the gaming site accounts for 15% of the social network's revenue. The two companies are joined at the hip and they're feeding off each other's slide, though Facebook's stock actually rose yesterday as Zynga's tumbled.

The gamer has made a number of missteps on its own, though, such as introducing a raft of new games that were too much like others it already peddles, so that the lack of differentiation allowed none of them to stick. Then it overpaid for OMGPOP's Draw Something, spending $180 million on a time-waster that had over 14 million users -- only to watch it drop to 5.6 million daily active players. It might be Zynga's third-biggest game on Facebook, but that's not a way to build a successful brand. It's also facing growing competition from more traditional game makers like Electronic Arts (NYSE: EA) and Disney (NYSE: DIS), which have the benefit of not being heavily reliant upon the social networking site should it falter.

It was only two weeks ago that I rated Zynga to underperform the market on CAPS, believing as I did that Facebook's foibles would ricochet back at it, and vice versa. The stock has lost 30% of its value since then and is down almost 50% year to date. I'll be maintaining my underperform CAPScall here, as there seems little to suggest it can turn around anytime soon.

That's also what the CAPS All-Stars apparently believe, as three-quarters of those rating the gaming company think it will continue to lose to the markets. But tell me in the comments section below whether you think Zynga's been zinged once too often, then add its stock to your watchlist to see whether it can come up with a game that will not only keep a player's attention but attract others to it as well.

Ready for a resurrection
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