This series, brought to you by Yahoo! Finance, looks at which upgrades and downgrades make sense, and which ones investors should act on. Today, the three most sensible analyst actions involve upgrades on Pandora Media (Nasdaq: P) and TIBCO Software (Nasdaq: TIBX), but also a downgrade on Life Technologies (Nasdaq: LIFE). Read on for all the juicy details.

What's in Pandora's box?
Raymond James has been cautious on Internet media expert Pandora but is changing its tune to "buy" based on a survey it conducted on Pandora's target market. The $14 price target is about 30% ahead of today's prices.

After balloting 422 Internet users, the firm found that Pandora's adoption is well ahead of upstarts like Spotify and second only to far-and-away leader Apple's (Nasdaq: AAPL) iTunes. Moreover, respondents said that they plan to increase their Pandora usage fatter than nearly any other online music application.

Increased use is always nice, but the real meat of Raymond James' argument comes in the prediction of stronger advertising sales. In short, there's plenty of room to increase audio advertising before Pandora matches the ad saturation of FM radio, the company is hiring more ad sales staff, and new audience measurement tools should help Pandora selling ad space to traditional radio advertisers. Moreover, the elections should increase ad sales because of rising volumes of political ads -- a very investable idea indeed. All of these items should lighten the pressure on Pandora's deeply crimson bottom line.

Run for your Life
Medical device all-rounder Life Technologies could use some relief. Goldman Sachs dropped a "sell" rating on the stock, noting a variety of challenges on the horizon.

Goldman's $38 target price sits about 16% below today's going rates. The firm sees weak academic funding putting cyclical pressure on the stock even as key products aren't as profitable as they should be -- a "structural" headwind in Goldman's terms.

Life Technologies may look cheap these days, but Goldman worries that it's more of a value trap than a real bargain. "We do not think valuation (below both peer and historical averages) is a sufficient upside catalyst and remind investors that Life Technologies has held a depressed relative valuation for the last two years," the firm says.

Now, Life Technologies does carry a perfect five out of five CAPS stars -- but much of that love comes from rock-bottom valuations. Fellow Fool Travis Hoium worries that the company is becoming a seller of commodity products, with shrinking margins on the way. "I've seen too many companies build up hope that their technology will be the best thing since sliced bread, and they rarely pan out the way you expect," Travis says. "I wouldn't make an underperform call here; I would just stay away from this stock altogether."

Words to live by, my friend.

That's the best kind of "buy"
Boutique firm Hilliard Lyons boosted Tibco to a "long-term buy," based on last week's Street-thumping earnings report.

Really, what's not to love? Despite currency headwinds and general weakness in Tibco's key European markets, the maker of data management and analysis software reported 14% higher second-quarter sales year over year and 26% stronger earnings. The company has crushed analyst targets for 16 quarters running, and there's no sign of a slowdown anytime soon.

Not content to rest on his laurels, CEO Vivek Ranadive said that he's still not satisfied with Tibco's sales performance in North America and made some changes to the sales force here. The excitement about strong opportunities is "palpable" in the domestic division, Ranadive told me in a one-on-one call. "And the best part is they all feel like they're not doing enough," he explained. "They're leaving a lot of money on the table."

Strong words from a company that has no trouble beating Wall Street targets, but there you go. After the earnings-induced price jump, you can still buy Tibco shares at a 12% discount from 52-week highs. Hilliard Lyons is smart to take a bullish long-term position here.

Fool contributor Anders Bylund holds no position in any of the companies mentioned. Check out Anders' holdings and bio, or follow him on Twitter and Google+. The Fool owns shares of Apple. Motley Fool newsletter services have recommended buying shares of Apple and TIBCO Software. Motley Fool newsletter services have recommended creating a bull call spread position in Apple. The Motley Fool has a disclosure policy.

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