According to The Sunday Telegraph, unnamed sources are saying that Yahoo CEO Marissa Mayer and Facebook COO Sheryl Sandberg have been discussing how the two companies can work together on a search engine. However, Kara Swisher at AllThingsD said her sources say the two companies are not talking about a search partnership, and that Microsoft won’t let Yahoo out of its long-term contract. “Forging an alliance with Yahoo! would allow the social network to take a major leap forward in search, ensuring it remains central to its users’ lives and helping to target advertising more efficiently,” The Sunday Telegraph notes. Yahoo would also benefit from the partnership, as its search engine has struggled in its fight to take share from Google. (CNET, The Telegraph)