Who is the biggest threat to Google (Nasdaq: GOOG)? What is the future of search? Will advertisers leave Google? I recently asked Michael Copeland, author of the Fortune cover story, "Google: The Search Party Is Over."  

Mac Greer: The article is entitled, Google: The Search Party Is Over.  So Michael, who or what crashed the party?

Michael Copeland: I would say the whole social media world crashed the party. So Facebook, Twitter, LinkedIn, Groupon, and social commerce along with Steve Jobs and the iPhone app economy --- they crashed the search party as well. What is gathering a lot of interest in some ways can be a substitution for a search. As more and more people are spending more and more time doing these things --- asking the question of their friends than asking the question of a search box --- advertisers are going to start to follow as well.

Greer: But in fairness to Google, in the case of a Facebook, we don't yet know if they can make money and if they can make more money than that.

Copeland: Yeah, the other day Facebook just launched Facebook Questions, which clearly they are trying to kind of push that substitution for key word search or desktop search that Google owns. And yeah, it's an open question whether Facebook, although they are making money from what we can tell, can get as big and monetize as efficiently as Google has with desktop search. But clearly there is a big shift in the Web and how we use it, and much of that doesn't include typical, traditional core search.

Greer: And if Google could eliminate one of these following three competitors, who do you think they would eliminate and why? Apple (Nasdaq: AAPL), Microsoft (Nasdaq: MSFT) or Facebook?

Copeland: Well, I'll put it this way. I think they have eliminated Microsoft on many levels already. I would say Facebook, because Facebook is the company that maybe plays most directly against them. Apple still makes great hardware, and Google benefits from the use of Apple hardware, even if the IOS kind of ecosystem competes against them. But I think the largest and fastest growing direct competitor for [Google] is Facebook. There are lots of ex-Googlers at Facebook as well, so I would say Facebook is what they would go after just so they can own the Web in the way that they have become used to. I think Apple sort of operates in its own sphere a little bit outside of it, but it is an open question as to whether Steve Jobs' vision of this IOS world, which is, as we know, a more closed world, prevails. I tend to think that ultimately it doesn't and that the sort of open-Web version that maybe Facebook and Google more embody, is the way that things will head in the long run.

Greer: You quote Debra Williamson, a senior analyst with e-Marketers. She says, "Facebook has Google in its sights. Advertisers get the best of both worlds: a mass audience, but also the ability to target more than anyone else."  So, Michael, if you are an advertiser, at what point, if ever, do you start shifting those ad dollars from Google to Facebook?

Copeland: Well, I think you are starting to see the shift now, especially in the display ads. As I mentioned, Facebook and Facebook Questions is a play to get the search advertising advertisers coming over to Facebook, too. So you have got display advertising already going to Facebook and that is a growing segment of online advertising. And if somebody gets it right, it is going to be massive. And then with Facebook Questions, you might have their bid to get kind of keyword search stuff going too over at Facebook. And clearly if Facebook starts serving up its own ads, which you can imagine, across the Web to sort of third-party sites, that is something I would be really worried about if I were Google. I think if anything, advertisers are going to have to figure out how they are going to split their advertising budgets going forward. There is going to be a split in advertising dollars away from solely search-related keyword advertising to more display and then some of these social sites.

If Facebook is the next Google then who is the next Steve Jobs?