Selling out to Yahoo has one huge advantage. They'll run your brainchild in to the ground so quickly that your non-compete clause probably amounts to nothing.

Kidding aside, Yahoo is a 'mixed bag', they've done some good acquisitions and made some headway, but they also literally killed a bunch of companies they took over through a combination of neglect and budgetary constraints.

If you sell out to Yahoo you know that that's the risk.