The bottom line here: most people are comfortable Googling. Google is deeply entrenched in the hearts and minds of users. It may take awhile for the Microsoft/Yahoo partnership to be put into practice. The deal still has to get the green light from regulators, which could take months. Expect Google to raise a stink as well. Both Microsoft and Yahoo said they hope to close the deal in early 2010.
Is there any good news for users in the deal? Google will be facing a more formidable foe that will slowly steal market share (keyword: slowly). The search king will likely be challenged and will innovate, creating better search to stay on top.
It could take two years, but the Microsoft/Yahoo partnership could awaken a renewed sense of urgency in Google, famous for its unrushed "beta" apps and features.
But right now this looks like a money grab for two wounded tech giants, not better search for you and me.