As an investor, it doesn't pay to follow the crowd.

In this series, though, we highlight a possible exception -- the collective wisdom of our Motley Fool CAPS community. Read the next section if you're not familiar with our methodology. Skip it if you want to go straight to the results.

Why this crowd is different
Jumping into a stock because your rich neighbor did, or because you heard about it from your friend's uncle who used to work on Wall Street, or because CNBC has been talking about it nonstop, is a recipe for disaster.

If there's one thing I've learned as a stock analyst, it's that any stock can be gussied up to sound like a world-beater. If there's a second thing I've learned, it's that being a smart person doesn't make you a good investor.

In the hands of a smart person with good communication skills, the never-were and never-will-be stocks sound like tickets to instant fortune. The ancient Greek philosophers made the distinction between rhetoric and knowledge. The former is convincing; the latter is true.

That's why we factor in track records in our Motley Fool CAPS community. We invite everyone to give stocks an outperform (i.e., a "buy") or underperform rating (i.e., a "sell") in CAPS. We then use those opinions to calculate a rating for each stock -- from one to five stars (five being the best). But -- and this is a big distinction -- we give more weight to the opinions of folks whose picks have performed well in the past.

The top 7 ETF buys
So, with that methodology as prelude, I present to you the top seven ETFs based on the number of CAPS members who have rated the stock an outperform. Only ETFs garnering four- or five-star ratings are included.

Company

Market Capitalization (in millions)

Outperform Picks

CAPS Rating (out of 5)

iShares MSCI Brazil Index Fund (NYSE: EWZ)

      $9,315

     2,072

*****

Vanguard Emerging Markets Stock Index Fund (NYSE: VWO)

     $29,421

     1,455

*****

iShares Silver Trust (NYSE: SLV)

      $5,316

     1,389

****

PowerShares WilderHill Clean Energy (NYSE: PBW)

        $533

     1,032

****

iShares MSCI Emerging Markets Index Fund (NYSE: EEM)

     $39,673

      977

****

PowerShares Water Resources (NYSE: PHO)

      $1,020

      810

*****

PowerShares DB Agriculture Trust (NYSE: DBA)

      $1,973

      751

*****

Source: Motley Fool CAPS as of Aug. 12.

More CAPS members think the iShares MSCI Brazil Index Fund is a buy than any other four- or five-star financial services players. Two other emerging markets ETFs are in the top seven as well. Do you think a different ETF belongs in the top seven? Or that a different ETF deserves to be the No. 1 buy? Make your thoughts known in CAPS by clicking here. Or just go there to do further research on one of these popular stocks.

As for me, I own shares of Vanguard's emerging markets ETF. I'll put my CAPS reputation where my money already is and give it an outperform rating today. You can see my CAPS profile here.