There's been a lot of buzz about the growing popularity of Microsoft 's (Nasdaq: MSFT) Bing, and rightfully so. Bing incorporates a snazzy interface, a monetarily enriching product search engine, and respectable search results. The massive ad campaign isn't going to hurt, either.

However, Bing is still far, far away from seriously contending for Google 's (Nasdaq: GOOG) paid-search throne. What if the real threat to Big G's dominance is homegrown? What if the call for panic is coming from inside its own house?

The notion may seem preposterous at first, but ReadWriteWeb's Bernard Lunn has done a great job presenting the challenges facing Google's breakthrough AdWords advertising and AdSense ad-syndicating platforms.

Elephants don't forget … usually
In his article "AdSense: The (Weak) Elephant in the Room," Lunn takes a look at the stumbling blocks in Google's advertising business from the perspective of advertisers, third-party publishers that distribute Google's ads, and the consumers of the online marketing.

I'm not necessarily worried about the advertisers. As long as Google remains the 800-pound gorilla, sponsors aren't going to walk away. They may bid less on keywords if the campaigns are less effective, but that decision ultimately depends on the consumers.

AdSense publishers, who embed Google-provided code that populates their sites with relevant ads, are another concern. Lunn fears that click fraud and mysteries behind the payout formulas may hurt the program that plasters those "ads by Google" notices throughout cyberspace.

Again, these aren't deal-breakers. Click fraud and the unrevealed revenue-sharing percentages have been a part of AdSense since its launch six years ago. Beyond the current lull that has affected the entire online advertising industry, AdSense has been growing steadily and remains the top monetization tool for most content sites.

Google has always policed for click fraud, but it's also self-correcting. Since advertisers can track marketing campaigns, they simply bid less -- or avoid the AdSense network entirely and go exclusively through Google-owned sites -- to offset the cheaters. Yes, that makes it critical for Google to crack down on click fraud for the program to succeed, but there's little reason to believe that it's a bigger problem today than it has been since 2003.

As for the secret formulas behind how Google shares the wealth, it's not a mystery in sum. Google paid out $1.23 billion to AdSense publishers from the $1.64 billion it collected from AdSense advertisers during its latest quarter -- a generous 75% slice.

Sure, everyone isn't treated to exactly three quarters out of every buck in leads that they deliver to Google. Larger publishers make more. Smaller publishers make less. If Google's payouts were truly out of whack, smaller rivals such as the Yahoo! (Nasdaq: YHOO) Publisher Network would be gaining ground.

They're not. This is still Google's game to lose.

Then we get to you
If advertisers and publishers could be happier but have nowhere else to go, what about you, me, and everyone else surfing through cyberspace? We're the third part of the powerful triumvirate that keeps Google ticking.

This is where Lunn's concerns do worry me. He boils everything down to three potential pitfalls. Continued...