Yahoo remains a very troubled company, and critics are (as usual, it seems) calling for CEO Marissa Mayer’s head. In the process of trying to sell itself, the company’s most recent Q2 figures have shown a $440m loss – and still no buyer. Verizon seemed most likely to purchase the company, adding it to its recent $4.4bn acquisition of AOL, although AT&T’s name has also been linked to the company – as well as that of Warren Buffet. Financial analysts typically expect the core Yahoo assets to fetch $4-$5bn, but some outliers have said as much as $8bn. But no buyer has emerged, leading to some apparent unease in the investor community. July 25 is the deadline for the final…