Search the Internet for term "gravy days," and you'll probably find Google (NASDAQ:GOOG) topping the results. The leading Internet search engine is only getting bigger, having grown its slice of the search market for eight straight months. It's enabled smaller websites to join the Google revolution through its AdSense third-party publisher network, and it continues to line up advertisers looking to reach an audience for as little as pennies a lead.

Sure, Yahoo! (NASDAQ:YHOO), Motley Fool Inside Value pick Microsoft (NASDAQ:MSFT), and IAC/InterActiveCorp (NASDAQ:IACI) are all promoting their own unique search offerings. But Google is still the top dog until proven otherwise.

That doesn't mean that Google is golden. It's had its share of controversy, and even some of the most ardent fans have questioned the stock's valuation.

That's the ideal backdrop for this week's bout. When it comes to Google, not all Fools agree. John Bluis is bullish, but Chuck Saletta feels that the shares are headed for a fall.

Does Google belong in your portfolio? That's what this week's Duel is all about.

Duel on!