The market may take Wall Street analysts' upgrades seriously -- at least for a day or two -- but here at The Motley Fool, we don't. Instead, we pay much closer attention to the collective knowledge of our 170,000-plus Motley Fool CAPS members. When they upgrade a stock, I like to take a second look to see why.

I've listed three stocks that our CAPS members have upgraded to a lofty four- or five-star rating over the past six months.

Company

Rating 6 Months Ago (out of 5)

Rating Today

My Watchlist

Antares Pharma (AMEX: AIS) ** ***** Add to My Watchlist
UR-Energy (AMEX: URG) ** **** Add to My Watchlist
Transportadora de Gas del Sur S.A. (NYSE: TGS) ** **** Add to My Watchlist

Data from Motley Fool CAPS as of July, 13 2011.

A risk worth taking in pharma
Pharmaceutical stocks are all about finding potential, and investors are seeing a bright future ahead for Antares Pharma. The company's Anturol is still waiting for FDA approval, but there is growing optimism about the drug's future. Watson Pharmaceuticals recently signed a licensing deal to market the drug in the U.S. and Canada if the FDA gives it the green light. As CAPS member dgoldmeier points out, "If Antares gets approval to market their gel for overactive bladders later this year this company can turn into a cash cow over the next few years."

There is competition with Pfizer (NYSE: PFE) already in the space, but with a $2 billion potential market, Antares' innovative gel could give this investment a boost.

A contrarian view of energy
Investors appear to have gone value hunting in UR-Energy over the past six months. When the stock was riding high six months ago, CAPS investors had given it a lowly two-star rating, but with uranium stocks suffering after the Japan nuclear disaster, UR-Energy is up to four stars as investors see better value.

Uranium producers and explorers such as Cameco (NYSE: CCJ), Uranerz Energy (AMEX: URZ), and UR-Energy have been hammered since the disaster. But most of the world's nuclear reactors are staying open, and uranium will still be needed in the future. That means plenty of opportunity for UR-Energy, and CAPS member Piambar makes a simple pitch by saying, "once the dust settles, uranium should do well." The contrarian investor in me tends to agree.

The fuel of the future
The combination of natural gas, liquid natural gas, and an emerging market in Argentina have turned Transportadora de Gas del Sur (TGS) into a CAPS favorite. As CAPS member jimnall2003 says:

When oil becomes prohibitively expensive, natural gas, and its transporters, will take over. Great future. If "top rated" investors are leaving they're missing the long-term gain.

Lots of investors are betting on natural gas, and companies such as TGS that process natural gas liquids will be able to leverage a growing appetite for this fuel. Clean Energy Fuels (Nasdaq: CLNE), which is helping deliver natural gas fuels to customers, is expanding infrastructure quickly here, and if the U.S. is successful, Argentina shouldn't be too far behind. That would play in TGS's favor.

Foolish bottom line
A stock upgraded to four or five stars has earned a little more due diligence, if not a spot on My Watchlist. A one- or two-star rating is worth a second look and may signal that it's time to sell. Either way, the collective wisdom of the CAPS community can help steer Fools toward winning investments.

Fool contributor Travis Hoium has no position in any company mentioned. You can follow Travis on Twitter at @FlushDrawFool, check out his personal stock holdings, or follow his CAPS picks at TMFFlushDraw.

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