Ironically, the resistance offered to the acquisition by Yahoo's board and upper management may have worked in Microsoft's favor, giving Ballmer a chance to realize that it's not in Microsoft's best interest to swallow Yahoo whole.

"Buying all of Yahoo made sense on paper, but the reality of making the two companies work together would have been a nightmare," Li said.

There are so many overlaps between the Microsoft Internet unit and Yahoo, that the integration would have been highly complex, requiring a lot of time and effort, when in fact Microsoft only needs the search portion, Li said.

Sensing that Microsoft's acquisition of Yahoo's search business is inevitable, Ballmer recently urged Yahoo to cooperate in getting it done "sooner rather than later."

Yahoo, with its stock in the $12 to $13 range, has much less leverage or negotiating power than it had at the start of 2008. Still, Yahoo would be in an even weaker position without a search business, so it should attempt to cut a more limited deal, similar to the one with Google, Sterling said.