Mike Zahalan writes with an update to last month's news that AOL and various private equity firms were exploring the possiblity of buying Yahoo. While talks between the companies have not officially gone much deeper, AOL has now hired financial advisers to analyze their options. Still, Kara Swisher writes at All Things Digital that the complexity of a deal between the two companies will be the biggest obstacle they have to overcome. "Among the issues being grappled with: Onerous tax implications around a variety of deals; a need for complete cooperation from too many players; and the realization that a hookup of AOL and Yahoo might cause more problems than it solves. 'It looks great conceptually and everyone gets all hot and bothered,' said one prominent investor who did his own strategizing about Yahoo and AOL. 'But when you actually do the numbers, you hit a pretty big wall of impossible.'"