Now is when the hard work begins for Microsoft and Yahoo, after finally getting the regulatory green light from the U.S. and the European Union to implement their ballyhooed search engine partnership.

The U.S. Department of Justice and the European Commission on Thursday both unconditionally approved Microsoft and Yahoo's plan to work together in the field of Internet search.

Google cofounder and President of Technology Sergey Brin made a surprise appearance at the Web 2.0 Summit on Thursday, answering a variety of questions on hot-button issues affecting the search company.

A Microsoft and Yahoo search deal, announced in July, will face an in-depth antitrust review from the U.S. Department of Justice, Microsoft has confirmed.

Yahoo hopes to remain relevant and competitive in the search engine market, battling for users not only against nemesis Google but also against its future search partner, Microsoft.

Yahoo's decision to use Microsoft's Bing search engine could cause a "strange bedfellows" competitive conflict between Microsoft and IBM in the enterprise search market.

Microsoft CEO Steve Ballmer was surprised that Wall Street reacted negatively to Yahoo's plan to hand over its Internet search and advertising reins to Microsoft, he said Thursday.

When Yahoo Inc. agreed to team up with Microsoft Corp. to better take on search giant Google Inc., some analysts said they wondered whether the online pioneer mistakenly sold its soul in the process.

Well, friends, sound the wedding bells: The longest-running courtship in the history of mankind has finally reached its climax. No July Fools' joke here -- Microsoft and Yahoo have agreed to tie the knot and form a search partnership.

The Microsoft Corp. and Yahoo Inc. courtship that has been taking place on and off for the past four years had grown as tiresome as the annual Brett Favre retirement watch.