Now that Google's (NASDAQ:GOOG) IPO has come and gone, with differing opinions of the relative success of the Dutch auction model, it's been relatively quiet over at the search engine's Mountain View, Calif., offices. Speculation, though, has been mounting over what Google may ultimately become. Fool contributor Rick Munarriz suggested it should become more like a portal.

Right now, the heady speculation seems to be coalescing around the idea of a Google Web browser.

To back up that idea, note that the company held a Mozilla Development Day on its campus, where programmers spent the day improving the renamed Netscape browser. The theory goes that building a new browser from the ground up might be unproductive, while adding to an already existing platform -- the open-source Mozilla, for example -- would be a huge kick-start.

Google's recent hiring spree is another sign that the company is moving to challenge Microsoft's (NASDAQ:MSFT) Internet Explorer superiority. Google snagged one of the main developers of Java, the Internet programming language, from Sun Microsystems (NASDAQ:SUNW); it brought on the lead developer of Avalon, the next-generation user interface for Internet Explorer; and it hired a few people who have been working on Internet Explorer itself.

Google has already added a number of enhancements to its search engine, such as searching for images and the photo organizer Picasa, and it has expanded into webmail with its Gmail service. There's also the local computer search utility for Windows users and the Deskbar, a utility that lets you search from within any application. Is a G-browser in the works? Well, Google has already snapped up the domain name

The promise of a Google browser would undoubtedly be the clean interface similar to its search engine. It would be an immediately recognizable brand, would be easy to use, and wouldn't muck up the inner workings of your computer. At least that's the theory -- or the rumor. Mozilla's Gecko rendering engine is just one open-source possibility. Another is KHTML, which is used for Apple's (NASDAQ:AAPL) Safari browser, as well as OmniWeb and Konqueror.

A G-browser would be able to tie in all of Google's offerings in a single, neat package: Gmail, Froogle, Blogger, and search. Would instant messaging be far off? The possibilities seem endless and would vault Google well beyond Yahoo! (NASDAQ:YHOO) or AOL (NYSE:TWX).

Whether it could ultimately supplant Internet Explorer as the premier Web browser is open to speculation. Yet there are plenty of people who are looking for someone -- anyone -- to offer a viable, competing product. There have been pretenders to the throne before. Does Google have the wherewithal to wear the crown?

Discuss your thoughts on Google becoming the Internet's No. 1 Web browser on the Google discussion board.

Fool contributor Rich Duprey wonders how an office complex metamorphosed into a "campus." He does not own any of the stocks mentioned in this article.