>>eg. buying youtube instead of making google video better.. I guess it is not the problem of technology, but market share that drived G! to buy utube. Also that buying makes a strong statement in the market, and gives it video lot of attention as well. They fear Yahoo will be able to maintain / steel most of its customers, becasue they offer a complete set of services (messenger, my yahoo, store, mail,...). So they feel the need to become a complete portal by acquiring specialised service providers with good market share.
G is the nets premier brand that viz a vie the market potential, has not yet 'got out of the starting gates' The upside adsense market is vast, with worldwide reach, don't worry the billions of dollars will be replaced By Trillions of Dollars of Revenue