Nielsen is out with its monthly list of the hottest Web properties, and June's results shouldn't surprise you.

  • Google (NASDAQ:GOOG) is the top dog when it comes to unique audience.
  • Facebook is stickier than flypaper -- although stickiness isn't everything.
  • IAC (NASDAQ:IACI) is a relative minnow when it comes to stickiness, but it reaches a larger audience than commercial sites such as eBay (NASDAQ:EBAY), Apple (NASDAQ:AAPL), and Amazon.com (NASDAQ:AMZN).
  • AOL isn't dead.
  • Microsoft (NASDAQ:MSFT) draws a bigger crowd than Yahoo! (NASDAQ:YHOO) does, but it can't keep folks hanging around as long.

Skim below the surface, and you can learn a lot from the numbers if you're an investor. Let's look at the audience numbers for June, as well as the average amount of time spent on a company's sites during the entire month.

Parent

Unique Audience

Time Per Person (in Hours)

1. Google

155.6 million

2:31

2. Microsoft

139.1 million

2:12

3. Yahoo!

134.3 million

3:16

4. AOL

92.7 million

2:42

5. News Corp.

90.3 million

1:54

6. Facebook

87.3 million

4:40

7. IAC

67.3 million

0:20

8. eBay

67.2 million

1:18

9. Apple

59.7 million

1:19

10. Amazon

59.6 million

0:26

Source: Nielsen NetView.

Now let's dig into a few meaty takeaways.

Stickiness is overrated
Place Yahoo! and eBay on adjacent market-cap scales, and they'll weigh about the same. Each stock has a current market cap in the range of $20 billion to $21 billion. The usage metrics aren't even close, though.

Yahoo! commands an audience twice as large as eBay's. The average user also spends far less time on eBay (an average of an hour and 18 minutes) than on Yahoo! (3 hours and 16 minutes).

How can this be? If Yahoo! holds the attention of a larger crowd for a longer time, shouldn't it be the more valuable company? Nope. In fact, it's not even close. Despite the traffic disparity, eBay generates more revenue and earnings than Yahoo! does.

The key is that Yahoo!'s page views are for things like free e-mail or news, typically monetized by display advertising. eBay's page views often produce actionable fee-based events, such as auction listings and PayPal transactions.

Facebook is more popular than you think
Can Facebook be more popular than Google in this country? If you multiply the unique audience by the average amount of time spent on the company's portfolio of sites, the surprising answer is that it is now more popular.

The only site that would outrank Facebook in terms of the total time logged on the site last month, according to Nielsen's metrics, would be Yahoo! -- and it's a close race.

Again, this doesn't mean that Facebook is more valuable than Google, or only slightly less valuable than Yahoo! The fact that Google commands a market cap several times the size of Yahoo! should illustrate the flaw in the reasoning. It's not who you're drawing or even how long you're drawing them that counts; it's all about how you can monetize your audience.

If you spent 26 minutes shopping through Amazon's virtual storefront last month, that was far more valuable than nearly 4 hours and 40 minutes of updating statuses, texting with friends, and uploading family photographs through Facebook.

However, this state of affairs also spells the mother of all opportunities for Facebook. Now that it's brilliantly magnetic, what happens when it really turns on the charm? It's only a matter of time before more Web searches originate on Facebook, and friends provide the leads and referrals that sites such as Google and IAC are currently providing. Apple has captivated the imagination of developers with its App Store, but Facebook's app platform is just begging to be monetized accordingly.

As long as Facebook doesn't slip -- the way other social networks have in the past -- that laughable $15 billion valuation that was proposed in 2007 may one day be laughably too low.

The $135 billion question
Am I seriously suggesting that Facebook will one day top Google in terms of market cap? It probably won't come to that. Google will be smart enough to evolve or make Facebook an offer it can't refuse if it ever sees that trend taking shape. After all, Facebook has a better shot of nailing local search than even the almighty Google does, and Big G can't let that happen.  

Google would try a homegrown workaround at first, of course. YouTube keeps people hanging around, and it's taking baby steps toward socialization. YouTube has a better chance of successfully adding more social features than Google would have trying to turn its Orkut site into a legitimate contender.

So by the time Facebook has it all figured out, Google -- or someone else -- may have moved its cheese.

But why take that chance? Instead of having us media types nudging Google toward a buyout offer of Twitter, Facebook is the one that Google really needs to see on its arm.

Some cool widgets for your Facebook profile:

Google is a Motley Fool Rule Breakers selection. Apple, Amazon.com, and eBay are Motley Fool Stock Advisor picks. Microsoft and eBay are Motley Fool Inside Value pick. Try any of our Foolish newsletter services free for 30 days.

Longtime Fool contributor Rick Munarriz remembers when social networks were an offline endeavor. He owns no shares in any of the companies in this story and is also a member of the Rule Breakers analytical team, seeking out the next great growth stock early in its defiance. The Fool has a disclosure policy.