I'm sorry that Yahoo hasn't invested enough in evangelists to stop people like you from spreading FUD like this.
* Yahoo established a relationship with Microsoft. The relationship involves refactoring both Bing and Yahoo Search to use the same web index.
* The crawler, storage and serving infrastructure for web indexes are capital intensive. It has nothing to do with technology -- it amounts to buying up farmlands in Idaho to store millions of computers.
* Hence, it's simply about whoever has the largest pile of cash. Since Yahoo's pile of cash is tiny compared to Google, the ONLY way to stop Google from a monopoly is Microsoft.
* This lets Yahoo concentrate on improving search outside of the boring parts of search. They're calling this the "death of the 10 blue links". If you see yahoo search today, they're ahead of Google on this.
* Outsourcing capital-intensive parts allows Yahoo to innovate on things that they are VERY good at: content optimization, display advertising, and editorial content.
* Thanks to this deal, Yahoo also now owns 100% of the display advertising market outside of doubleclick. This includes all Microsoft properties. What's important to note is that Facebook has a display deal with Microsoft till 2011.
I hope that makes it clearer. Yahoo is not MS's bitch. MS is not Yahoo's bitch. This is a strategic partnership. This happens in business.