Back in July, when Microsoft walked away from Yahoo, conspiracy theorists surmised that the software giant would eventually come back to bid again at half the price. The Chief Yahoo - that's the title Jerry Yang is reclaiming after saying last night he would step down as CEO - is no longer in a position to block a deal, so it's fair to assume Microsoft and its bulging mound of cash could return for another bite. 
 
Yang has been talking with the board, which includes activist investor Carl Icahn, about stepping down since before Google pulled out of a search advertising deal with his company earlier this month, according to a person familiar with the talks. 
 
Yahoo's share price jumped after the news on Yang. That could just be relief that he is going, or it could be renewed hope of a deal. So a dealmaker could take the reins of the Internet company, which has already seen great swaths of its brain trust flee in the months since the initial Microsoft bid failed. 
 
A source said the process of finding a successor to Yang could take anywhere from four to 12 weeks, and analysts have suggested a star-studded cast of candidates, including former AOL chief Jon Miller, News Corp President and Chief Operating Officer Peter Chernin, former eBay Chief Executive Meg Whitman, former Yahoo COO Dan Rosensweig, and Yahoo President Sue Decker.
  Will Microsoft formally announce an offer for Yahoo?

Deals of the day:
* French warplane maker Dassault Aviation is in exclusive talks with Alcatel-Lucent to buy the telecoms equipment maker's 20.8 percent stake in radar maker Thales for about 1.52 billion euros ($1.92 billion).
 
* Britain's Carphone Warehouse may split off its telecoms arm to focus on its retail venture with U.S. group Best Buy, it said as it warned of tough trading. 
 
* British publishing and exhibitions group United Business Media, which abandoned a planned merger with UK peer Informa earlier this year, said it was buying Xinhua PR Newswire, China's largest corporate announcement service, for $6 million in cash.