Half of Yahoo's (YHOO) workforce should be focused on mobile (a current weak spot), says Marissa Mayer during her first call as CEO. Improving ad targeting and site integration are also named priorities. Mayer claims most of Yahoo's acquisitions will be in the sub-$100M range (MM and OPEN, reportedly drawing Yahoo's interest, are much bigger), and that Yahoo plans to continue working with Microsoft (NASDAQ:MSFT) in spite of "disappointment" with the search partnership. Shares +4.1% AH. (live blogs: I, II) (Q3 results: I, II)